fanotify-watch: Not really part of Bees, but a useful tool nonetheless

.gitignore

@@ -10,6 +10,3 @@ html/
 latex/
 make.log
 make.log.new
-localconf
-scripts/beesd
-scripts/beesd@.service

Makefile

@@ -1,58 +1,19 @@
-PREFIX ?= /
-LIBDIR ?= lib
-USR_PREFIX ?= $(PREFIX)/usr
-USRLIB_PREFIX ?= $(USR_PREFIX)/$(LIBDIR)
-SYSTEMD_LIB_PREFIX ?= $(PREFIX)/lib/systemd
-LIBEXEC_PREFIX ?= $(USRLIB_PREFIX)/bees
+default install all: lib src test README.html
 
-MARKDOWN := $(firstword $(shell which markdown markdown2 markdown_py 2>/dev/null || echo markdown))
+clean:
+	git clean -dfx
 
-# allow local configuration to override above variables
--include localconf
+.PHONY: lib src
 
-default all: lib src scripts test README.html
-
-clean: ## Cleanup
-	git clean -dfx -e localconf
-
-.PHONY: lib src test
-
-lib: ## Build libs
+lib:
 	$(MAKE) -C lib
 
-src: ## Build bins
 src: lib
 	$(MAKE) -C src
 
-test: ## Run tests
 test: lib src
 	$(MAKE) -C test
 
-scripts/%: scripts/%.in
-	sed -e's#@LIBEXEC_PREFIX@#$(LIBEXEC_PREFIX)#' -e's#@PREFIX@#$(PREFIX)#' "$<" >"$@"
-
-scripts: scripts/beesd scripts/beesd@.service
-
 README.html: README.md
-	$(MARKDOWN) README.md > README.html.new
+	markdown README.md > README.html.new
 	mv -f README.html.new README.html
-
-install_bees: ## Install bees + libs
-install_bees: lib src test
-	install -Dm644 lib/libcrucible.so $(DESTDIR)$(USRLIB_PREFIX)/libcrucible.so
-	install -Dm755 bin/bees	$(DESTDIR)$(LIBEXEC_PREFIX)/bees
-
-install_scripts: ## Install scipts
-install_scripts: scripts
-	install -Dm755 scripts/beesd $(DESTDIR)$(USR_PREFIX)/sbin/beesd
-	install -Dm644 scripts/beesd.conf.sample $(DESTDIR)$(PREFIX)/etc/bees/beesd.conf.sample
-	install -Dm644 scripts/beesd@.service $(DESTDIR)$(SYSTEMD_LIB_PREFIX)/system/beesd@.service
-
-install: ## Install distribution
-install: install_bees install_scripts
-
-help: ## Show help
-	@fgrep -h "##" $(MAKEFILE_LIST) | fgrep -v fgrep | sed -e 's/\\$$//' | sed -e 's/##/\t/'
-
-bees: all
-fly: install

README.md

@@ -1,52 +1,30 @@
 BEES
 ====
 
-Best-Effort Extent-Same, a btrfs dedup agent.
+Best-Effort Extent-Same, a btrfs deduplication daemon.
 
 About Bees
 ----------
 
-Bees is a block-oriented userspace dedup agent designed to avoid
-scalability problems on large filesystems.
+Bees is a daemon designed to run continuously on live file servers.
+Bees scans and deduplicates whole filesystems in a single pass instead
+of separate scan and dedup phases.  RAM usage does _not_ depend on
+unique data size or the number of input files.  Hash tables and scan
+progress are stored persistently so the daemon can resume after a reboot.
+Bees uses the Linux kernel's `dedupe_file_range` feature to ensure data
+is handled safely even if other applications concurrently modify it.
 
-Bees is designed to degrade gracefully when underprovisioned with RAM.
-Bees does not use more RAM or storage as filesystem data size increases.
-The dedup hash table size is fixed at creation time and does not change.
-The effective dedup block size is dynamic and adjusts automatically to
-fit the hash table into the configured RAM limit.  Hash table overflow
-is not implemented to eliminate the IO overhead of hash table overflow.
-Hash table entries are only 16 bytes per dedup block to keep the average
-dedup block size small.
+Bees is intentionally btrfs-specific for performance and capability.
+Bees uses the btrfs `SEARCH_V2` ioctl to scan for new data without the
+overhead of repeatedly walking filesystem trees with the POSIX API.
+Bees uses `LOGICAL_INO` and `INO_PATHS` to leverage btrfs's existing
+metadata instead of building its own redundant data structures.
+Bees can cope with Btrfs filesystem compression.  Bees can reassemble
+Btrfs extents to deduplicate extents that contain a mix of duplicate
+and unique data blocks.
 
-Bees does not require alignment between dedup blocks or extent boundaries
-(i.e. it can handle any multiple-of-4K offset between dup block pairs).
-Bees rearranges blocks into shared and unique extents if required to
-work within current btrfs kernel dedup limitations.
-
-Bees can dedup any combination of compressed and uncompressed extents.
-
-Bees operates in a single pass which removes duplicate extents immediately
-during scan.  There are no separate scanning and dedup phases.
-
-Bees uses only data-safe btrfs kernel operations, so it can dedup live
-data (e.g. build servers, sqlite databases, VM disk images).  It does
-not modify file attributes or timestamps.
-
-Bees does not store any information about filesystem structure, so it is
-not affected by the number or size of files (except to the extent that
-these cause performance problems for btrfs in general).  It retrieves such
-information on demand through btrfs SEARCH_V2 and LOGICAL_INO ioctls.
-This eliminates the storage required to maintain the equivalents of
-these functions in userspace.  It's also why bees has no XFS support.
-
-Bees is a daemon designed to run continuously and maintain its state
-across crahes and reboots.  Bees uses checkpoints for persistence to
-eliminate the IO overhead of a transactional data store.  On restart,
-bees will dedup any data that was added to the filesystem since the
-last checkpoint.
-
-Bees is used to dedup filesystems ranging in size from 16GB to 35TB, with
-hash tables ranging in size from 128MB to 11GB.
+Bees includes a number of workarounds for Btrfs kernel bugs to (try to)
+avoid ruining your day.  You're welcome.
 
 How Bees Works
 --------------
@@ -100,16 +78,18 @@ and some metadata bits).  Each entry represents a minimum of 4K on disk.
         1TB                16MB               1024K
        64TB                 1GB               1024K
 
-To change the size of the hash table, use 'truncate' to change the hash
-table size, delete `beescrawl.dat` so that bees will start over with a
-fresh full-filesystem rescan, and restart `bees'.
+It is possible to resize the hash table by changing the size of
+`beeshash.dat` (e.g. with `truncate`) and restarting `bees`.  This
+does not preserve all the existing hash table entries, but it does
+preserve more than zero of them--especially if the old and new sizes
+are a power-of-two multiple of each other.
 
 Things You Might Expect That Bees Doesn't Have
 ----------------------------------------------
 
-* There's no configuration file (patches welcome!).  There are some tunables
-hardcoded in the source that could eventually become configuration options.
-There's also an incomplete option parser (patches welcome!).
+* There's no configuration file or getopt command line option processing
+(patches welcome!).  There are some tunables hardcoded in the source
+that could eventually become configuration options.
 
 * There's no way to *stop* the Bees daemon.  Use SIGKILL, SIGTERM, or
 Ctrl-C for now.  Some of the destructors are unreachable and have never
@@ -134,6 +114,11 @@ performance by caching, but really fixing this requires rewriting the
 crawler to scan the btrfs extent tree directly instead of the subvol
 FS trees.
 
+* Bees had support for multiple worker threads in the past; however,
+this was removed because it made Bees too aggressive to coexist with
+other applications on the same machine.  It also hit the *slow backrefs*
+on N CPU cores instead of just one.
+
 * Block reads are currently more allocation- and CPU-intensive than they
 should be, especially for filesystems on SSD where the IO overhead is
 much smaller.  This is a problem for power-constrained environments
@@ -144,9 +129,6 @@ blocks, but has no defragmentation capability yet.  When possible, Bees
 will attempt to work with existing extent boundaries, but it will not
 aggregate blocks together from multiple extents to create larger ones.
 
-* It is possible to resize the hash table without starting over with
-a new full-filesystem scan; however, this has not been implemented yet.
-
 Good Btrfs Feature Interactions
 -------------------------------
 
@@ -162,11 +144,11 @@ Bees has been tested in combination with the following:
 * IO errors during dedup (read errors will throw exceptions, Bees will catch them and skip over the affected extent)
 * Filesystems mounted *with* the flushoncommit option
 * 4K filesystem data block size / clone alignment
-* 64-bit and 32-bit host CPUs (amd64, x86, arm)
+* 64-bit CPUs (amd64)
 * Large (>16M) extents
 * Huge files (>1TB--although Btrfs performance on such files isn't great in general)
 * filesystems up to 25T bytes, 100M+ files
-* btrfs read-only snapshots
+
 
 Bad Btrfs Feature Interactions
 ------------------------------
@@ -174,14 +156,16 @@ Bad Btrfs Feature Interactions
 Bees has not been tested with the following, and undesirable interactions may occur:
 
 * Non-4K filesystem data block size (should work if recompiled)
+* 32-bit CPUs (x86, arm)
 * Non-equal hash (SUM) and filesystem data block (CLONE) sizes (probably never will work)
-* btrfs send/receive (receive is probably OK, but send could be confused?)
+* btrfs read-only snapshots (never tested, probably wouldn't work well)
+* btrfs send/receive (receive is probably OK, but send requires RO snapshots.  See above)
 * btrfs qgroups (never tested, no idea what might happen)
 * btrfs seed filesystems (does anyone even use those?)
 * btrfs autodefrag mount option (never tested, could fight with Bees)
-* btrfs nodatacow/nodatasum inode attribute or mount option (bees skips all nodatasum files)
+* btrfs nodatacow mount option or inode attribute (*could* work, but might not)
 * btrfs out-of-tree kernel patches (e.g. in-band dedup or encryption)
-* btrfs-convert from ext2/3/4 (never tested, might run out of space or ignore significant portions of the filesystem due to sanity checks)
+* btrfs-convert from ext2/3/4 (never tested)
 * btrfs mixed block groups (don't know a reason why it would *not* work, but never tested)
 * open(O_DIRECT)
 * Filesystems mounted *without* the flushoncommit option
@@ -189,7 +173,7 @@ Bees has not been tested with the following, and undesirable interactions may oc
 Other Caveats
 -------------
 
-* btrfs balance will invalidate parts of the dedup hash table.  Bees will
+* btrfs balance will invalidate parts of the dedup table.  Bees will
   happily rebuild the table, but it will have to scan all the blocks
   again.
 
@@ -200,79 +184,41 @@ Other Caveats
 
 * Bees creates temporary files (with O_TMPFILE) and uses them to split
   and combine extents elsewhere in btrfs.  These will take up to 2GB
-  of disk space per thread during normal operation.
+  during normal operation.
 
 * Like all deduplicators, Bees will replace data blocks with metadata
-  references.  It is a good idea to ensure there is sufficient unallocated
-  space (see `btrfs fi usage`) on the filesystem to allow the metadata
-  to multiply in size by the number of snapshots before running Bees
-  for the first time.  Use
+  references.  It is a good idea to ensure there are several GB of
+  unallocated space (see `btrfs fi df`) on the filesystem before running
+  Bees for the first time.  Use
 
-        btrfs balance start -dusage=100,limit=N /your/filesystem
+        btrfs balance start -dusage=100,limit=1 /your/filesystem
 
-  where the `limit` parameter 'N' should be calculated as follows:
-
-	* start with the current size of metadata usage (from `btrfs fi
-	  df`) in GB, plus 1
-
-	* multiply by the proportion of disk space in subvols with
-	  snapshots (i.e. if there are no snapshots, multiply by 0;
-	  if all of the data is shared between at least one origin
-	  and one snapshot subvol, multiply by 1)
-
-	* multiply by the number of snapshots (i.e. if there is only
-	  one subvol, multiply by 0; if there are 3 snapshots and one
-	  origin subvol, multiply by 3)
-
-  `limit = GB_metadata * (disk_space_in_snapshots / total_disk_space) * number_of_snapshots`
-
-  Monitor unallocated space to ensure that the filesystem never runs out
-  of metadata space (whether Bees is running or not--this is a general
-  btrfs requirement).
+  If possible, raise the `limit` parameter to the current size of metadata
+  usage (from `btrfs fi df`) plus 1.
 
 
 A Brief List Of Btrfs Kernel Bugs
 ---------------------------------
 
-Missing features (usually not available in older LTS kernels):
+Fixed bugs:
 
 * 3.13: `FILE_EXTENT_SAME` ioctl added.  No way to reliably dedup with
   concurrent modifications before this.
 * 3.16: `SEARCH_V2` ioctl added.  Bees could use `SEARCH` instead.
 * 4.2: `FILE_EXTENT_SAME` no longer updates mtime, can be used at EOF.
-
-Future features (kernel features Bees does not yet use, but may rely on
-in the future):
-
-* 4.14: `LOGICAL_INO_V2` allows userspace to create forward and backward
-  reference maps to entire physical extents with a single ioctl call,
-  and raises the limit of 2730 references per extent.  Bees has not yet
-  been rewritten to take full advantage of these features.
-
-Bug fixes (sometimes included in older LTS kernels):
-
-* Bugs fixed prior to 4.4.3 are not listed here.
-* 4.5: hang in the `INO_PATHS` ioctl used by Bees.
-* 4.5: use-after-free in the `FILE_EXTENT_SAME` ioctl used by Bees.
-* 4.6: lost inodes after a rename, crash, and log tree replay
-  (triggered by the fsync() while writing `beescrawl.dat`).
+  Kernel deadlock bugs fixed.
 * 4.7: *slow backref* bug no longer triggers a softlockup panic.  It still
-  takes too long to resolve a block address to a root/inode/offset triple.
-* 4.10: reduced CPU time cost of the LOGICAL_INO ioctl and dedup
-  backref processing in general.
-* 4.11: yet another dedup deadlock case is fixed.
-* 4.14: backref performance improvements make LOGICAL_INO even faster.
+  too long to resolve a block address to a root/inode/offset triple.
 
-Unfixed kernel bugs (as of 4.11.9) with workarounds in Bees:
+Unfixed kernel bugs (as of 4.5.7) with workarounds in Bees:
 
-* *slow backrefs* (aka toxic extents): If the number of references to a
-  single shared extent within a single file grows above a few thousand,
-  the kernel consumes CPU for minutes at a time while holding various
-  locks that block access to the filesystem.  Bees avoids this bug by
-  measuring the time the kernel spends performing certain operations
-  and permanently blacklisting any extent or hash where the kernel
-  starts to get slow.  Inside Bees, such blocks are marked as 'toxic'
-  hash/block addresses.  *Needs to be retested after v4.14.*
+* *slow backref*: If the number of references to a single shared extent
+  within a single file grows above a few thousand, the kernel consumes CPU
+  for up to 40 uninterruptible minutes while holding various locks that
+  block access to the filesystem.  Bees avoids this bug by measuring the
+  time the kernel spends performing certain operations and permanently
+  blacklisting any extent or hash where the kernel starts to get slow.
+  Inside Bees, such blocks are marked as 'toxic' hash/block addresses.
 
 * `LOGICAL_INO` output is arbitrarily limited to 2730 references
   even if more buffer space is provided for results.  Once this number
@@ -283,29 +229,32 @@ Unfixed kernel bugs (as of 4.11.9) with workarounds in Bees:
   This places an obvious limit on dedup efficiency for extremely common
   blocks or filesystems with many snapshots (although this limit is
   far greater than the effective limit imposed by the *slow backref* bug).
-  *Fixed in v4.14.*
-
-* `LOGICAL_INO` on compressed extents returns a list of root/inode/offset
-  tuples matching the extent bytenr of its argument.  On uncompressed
-  extents, any r/i/o tuple whose extent offset does not match the
-  argument's extent offset is discarded, i.e. only the single 4K block
-  matching the argument is returned, so a complete map of the extent
-  references requires calling `LOGICAL_INO` for every single block of
-  the extent.  This is undesirable behavior for Bees, which wants a
-  list of all extent refs referencing a data extent (i.e. Bees wants
-  the compressed-extent behavior in all cases).  *Fixed in v4.14.*
-
-* `LOGICAL_INO` is only called from one thread at any time per process.
-  This means at most one core is irretrievably stuck in this ioctl.
 
 * `FILE_EXTENT_SAME` is arbitrarily limited to 16MB.  This is less than
   128MB which is the maximum extent size that can be created by defrag
   or prealloc.  Bees avoids feedback loops this can generate while
   attempting to replace extents over 16MB in length.
 
-* If the `fsync()` in `BeesTempFile::make_copy` is removed, the filesystem
-  hangs within a few hours, requiring a reboot to recover.  On the other
-  hand, the `fsync()` only costs about 8% of overall performance.
+* `DEFRAG_RANGE` is useless.  The ioctl attempts to implement `btrfs
+  fi defrag` in the kernel, and will arbitrarily defragment more or
+  less than the range requested to match the behavior expected from the
+  userspace tool.  Bees implements its own defrag instead, copying data
+  to a temporary file and using the `FILE_EXTENT_SAME` ioctl to replace
+  precisely the specified range of offending fragmented blocks.
+
+* When writing BeesStringFile, a crash can cause the directory entry
+  `beescrawl.UUID.dat.tmp` to exist without a corresponding inode.
+  This directory entry cannot be renamed or removed; however, it does
+  not prevent the creation of a second directory entry with the same
+  name that functions normally, so it doesn't prevent Bees operation.
+
+  The orphan directory entry can be removed by deleting its subvol,
+  so place BEESHOME on a separate subvol so you can delete these orphan
+  directory entries when they occur (or use btrfs zero-log before mounting
+  the filesystem after a crash).
+
+* If the fsync() BeesTempFile::make_copy is removed, the filesystem
+  hangs within a few hours, requiring a reboot to recover.
 
 Not really a bug, but a gotcha nonetheless:
 
@@ -316,60 +265,14 @@ Not really a bug, but a gotcha nonetheless:
   children* until the FD is closed.  Bees avoids this gotcha by closing
   all of the FDs in its directory FD cache every 15 minutes.
 
-* If a file is deleted while Bees is caching an open FD to the file,
-  Bees continues to scan the file.  For very large files (e.g. VM
-  images), the deletion of the file can be delayed indefinitely.
-  To limit this delay, Bees closes all FDs in its file FD cache every
-  15 minutes.
 
-Installation
-============
 
-Bees can be installed by following one these instructions:
-
-Arch package
+Requirements
 ------------
 
-Bees is availabe in Arch Linux AUR. Install with:
+* C++11 compiler (tested with GCC 4.9)
 
-`$ pacaur -S bees-git`
-
-Gentoo ebuild
--------------
-
-Bees is available as a Gentoo ebuild. Just copy `bees-9999.ebuild` from
-`contrib/gentoo` including the `files` subdirectory to your local
-overlay category `sys-fs`.
-
-You can copy the ebuild to match a Bees version number, and it will
-build that tagged version. It is partly supported since v0.5,
-previous versions won't work.
-
-Build from source
------------------
-
-Build with `make`. The build produces `bin/bees` and `lib/libcrucible.so`,
-which must be copied to somewhere in `$PATH` and `$LD_LIBRARY_PATH`
-on the target system respectively.
-
-It will also generate `scripts/beesd@.service` for systemd users. This
-service makes use of a helper script `scripts/beesd` to boot the service.
-Both of the latter use the filesystem UUID to mount the root subvolume
-within a temporary runtime directory.
-
-### Ubuntu 16.04 - 17.04:
-`$ apt -y install build-essential btrfs-tools uuid-dev markdown && make`
-
-### Ubuntu 14.04:
-You can try to carry on the work done here: https://gist.github.com/dagelf/99ee07f5638b346adb8c058ab3d57492
-
-Dependencies
-------------
-
-* C++11 compiler (tested with GCC 4.9 and 6.2.0)
-
-  Sorry.  I really like closures and shared_ptr, so support
-  for earlier compiler versions is unlikely.
+  Sorry.  I really like closures.
 
 * btrfs-progs (tested with 4.1..4.7)
 
@@ -378,25 +281,34 @@ Dependencies
 
 * libuuid-dev
 
-  This library is only required for a feature that was removed after v0.1.
-  The lingering support code can be removed.
+  TODO: remove the one function used from this library.
+  It supports a feature Bees no longer implements.
 
-* Linux kernel 4.4.3 or later
+* Linux kernel 4.2 or later
 
   Don't bother trying to make Bees work with older kernels.
   It won't end well.
 
-* markdown
+* 64-bit host and target CPU
 
-* util-linux version that provides `blkid` command for the helper
-  script `scripts/beesd` to work
+  This code has never been tested on a 32-bit target CPU.
+
+  A 64-bit host CPU may be required for the self-tests.
+  Some of the ioctls don't work properly with a 64-bit
+  kernel and 32-bit userspace.
+
+Build
+-----
+
+Build with `make`.
+
+The build produces `bin/bees` and `lib/libcrucible.so`, which must be
+copied to somewhere in `$PATH` and `$LD_LIBRARY_PATH` on the target
+system respectively.
 
 Setup
 -----
 
-If you don't want to use the helper script `scripts/beesd` to setup and
-configure bees, here's how you manually setup bees.
-
 Create a directory for bees state files:
 
         export BEESHOME=/some/path
@@ -408,49 +320,17 @@ of 16M).  This example creates a 1GB hash table:
         truncate -s 1g "$BEESHOME/beeshash.dat"
         chmod 700 "$BEESHOME/beeshash.dat"
 
-bees can only process the root subvol of a btrfs (seriously--if the
-argument is not the root subvol directory, Bees will just throw an
-exception and stop).
-
-Use a bind mount, and let only bees access it:
-
-	UUID=3399e413-695a-4b0b-9384-1b0ef8f6c4cd
-	mkdir -p /var/lib/bees/$UUID
-	mount /dev/disk/by-uuid/$UUID /var/lib/bees/$UUID -osubvol=/
-
-If you don't set BEESHOME, the path ".beeshome" will be used relative
-to the root subvol of the filesystem.  For example:
-
-	btrfs sub create /var/lib/bees/$UUID/.beeshome
-	truncate -s 1g /var/lib/bees/$UUID/.beeshome/beeshash.dat
-	chmod 700 /var/lib/bees/$UUID/.beeshome/beeshash.dat
-
-You can use any relative path in BEESHOME.  The path will be taken
-relative to the root of the deduped filesystem (in other words it can
-be the name of a subvol):
-
-	export BEESHOME=@my-beeshome
-	btrfs sub create /var/lib/bees/$UUID/$BEESHOME
-	truncate -s 1g /var/lib/bees/$UUID/$BEESHOME/beeshash.dat
-	chmod 700 /var/lib/bees/$UUID/$BEESHOME/beeshash.dat
-
 Configuration
 -------------
 
 The only runtime configurable options are environment variables:
 
 * BEESHOME: Directory containing Bees state files:
- * beeshash.dat  | persistent hash table.  Must be a multiple of 16M.
-                   This contains 16-byte records:  8 bytes for CRC64,
-                   8 bytes for physical address and some metadata bits.
- * beescrawl.dat | state of SEARCH_V2 crawlers.  ASCII text.
- * beesstats.txt | statistics and performance counters.  ASCII text.
-* BEESSTATUS: File containing a snapshot of current Bees state:  performance
-  counters and current status of each thread.  The file is meant to be
-  human readable, but understanding it probably requires reading the source.
-  You can watch bees run in realtime with a command like:
-
-	watch -n1 cat $BEESSTATUS
+ * beeshash.dat         | persistent hash table (must be a multiple of 16M)
+ * beescrawl.`UUID`.dat | state of SEARCH_V2 crawlers
+ * beesstats.txt        | statistics and performance counters
+* BEESSTATS: File containing a snapshot of current Bees state (performance
+  counters and current status of each thread).
 
 Other options (e.g. interval between filesystem crawls) can be configured
 in src/bees.h.
@@ -458,27 +338,39 @@ in src/bees.h.
 Running
 -------
 
-Reduce CPU and IO priority to be kinder to other applications sharing
-this host (or raise them for more aggressive disk space recovery).  If you
-use cgroups, put `bees` in its own cgroup, then reduce the `blkio.weight`
-and `cpu.shares` parameters.  You can also use `schedtool` and `ionice`
-in the shell script that launches `bees`:
+We created this directory in the previous section:
+
+        export BEESHOME=/some/path
+
+Use a tmpfs for BEESSTATUS, it updates once per second:
+
+        export BEESSTATUS=/run/bees.status
+
+bees can only process the root subvol of a btrfs (seriously--if the
+argument is not the root subvol directory, Bees will just throw an
+exception and stop).
+
+Use a bind mount, and let only bees access it:
+
+        mount -osubvol=/ /dev/<your-filesystem> /var/lib/bees/root
+
+Reduce CPU and IO priority to be kinder to other applications
+sharing this host (or raise them for more aggressive disk space
+recovery).  If you use cgroups, put `bees` in its own cgroup, then reduce
+the `blkio.weight` and `cpu.shares` parameters.  You can also use
+`schedtool` and `ionice` in the shell script that launches `bees`:
 
         schedtool -D -n20 $$
         ionice -c3 -p $$
 
 Let the bees fly:
 
-	for fs in /var/lib/bees/*-*-*-*-*/; do
-		bees "$fs" >> "$fs/.beeshome/bees.log" 2>&1 &
-	done
+        bees /var/lib/bees/root >> /var/log/bees.log 2>&1
 
 You'll probably want to arrange for /var/log/bees.log to be rotated
 periodically.  You may also want to set umask to 077 to prevent disclosure
 of information about the contents of the filesystem through the log file.
 
-There are also some shell wrappers in the `scripts/` directory.
-
 
 Bug Reports and Contributions
 -----------------------------
@@ -494,6 +386,6 @@ You can also use Github:
 Copyright & License
 ===================
 
-Copyright 2015-2017 Zygo Blaxell <bees@furryterror.org>.
+Copyright 2015-2016 Zygo Blaxell <bees@furryterror.org>.
 
 GPL (version 3 or later).

contrib/gentoo/bees-9999.ebuild

@@ -1,44 +0,0 @@
-# Copyright 1999-2018 Gentoo Foundation
-# Distributed under the terms of the GNU General Public License v2
-
-EAPI=6
-
-inherit git-r3 eutils multilib
-
-DESCRIPTION="Best-Effort Extent-Same, a btrfs dedup agent"
-HOMEPAGE="https://github.com/Zygo/bees"
-
-if [[ ${PV} == "9999" ]] ; then
-	EGIT_REPO_URI="https://github.com/kakra/bees.git"
-	EGIT_BRANCH="integration"
-else
-	SRC_URI="https://github.com/Zygo/bees/archive/v${PV}.tar.gz -> ${P}.tar.gz"
-fi
-
-PATCHES="
-	${FILESDIR}/v0.5-gentoo_build.patch
-"
-
-LICENSE="GPL-3"
-SLOT="0"
-KEYWORDS=""
-IUSE=""
-
-COMMON_DEPEND="
-	>=sys-apps/util-linux-2.30.2
-	>=sys-devel/gcc-4.9
-	>=sys-fs/btrfs-progs-4.1
-"
-DEPEND="
-	${COMMON_DEPEND}
-	|| ( dev-python/markdown dev-python/markdown2 )
-"
-RDEPEND="${COMMON_DEPEND}"
-
-DOCS="README.md COPYING"
-HTML_DOCS="README.html"
-
-src_prepare() {
-	default
-	echo LIBDIR=$(get_libdir) >>${S}/localconf
-}

contrib/gentoo/files/v0.5-gentoo_build.patch

@@ -1,20 +0,0 @@
-diff --git a/localconf b/localconf
-new file mode 100644
-index 0000000..7705cbb
---- /dev/null
-+++ b/localconf
-@@ -0,0 +1,2 @@
-+PREFIX=/
-+LIBEXEC_PREFIX=/usr/libexec
-diff --git a/makeflags b/makeflags
-index f5983cb..0348623 100644
---- a/makeflags
-+++ b/makeflags
-@@ -1,4 +1,3 @@
--CCFLAGS  = -Wall -Wextra -Werror -O3 -march=native -I../include -ggdb -D_FILE_OFFSET_BITS=64
--# CCFLAGS  = -Wall -Wextra -Werror -O0 -I../include -ggdb -fpic -D_FILE_OFFSET_BITS=64
--CFLAGS   = $(CCFLAGS) -std=c99
--CXXFLAGS = $(CCFLAGS) -std=c++11 -Wold-style-cast
-+CCFLAGS  = -O3 -I../include -fpic -D_FILE_OFFSET_BITS=64
-+CFLAGS   += $(CCFLAGS) -std=c99
-+CXXFLAGS += $(CCFLAGS) -std=c++11 -Wold-style-cast

include/crucible/bool.h

@@ -0,0 +1,13 @@
+#ifndef CRUCIBLE_BOOL_H
+#define CRUCIBLE_BOOL_H
+
+namespace crucible {
+	struct DefaultBool {
+		bool m_b;
+		DefaultBool(bool init = false) : m_b(init) {}
+		operator bool() const { return m_b; }
+		bool &operator=(const bool &that) { return m_b = that; }
+	};
+}
+
+#endif // CRUCIBLE_BOOL_H

include/crucible/btrfs.h

@@ -130,7 +130,7 @@
 	};
 
 #endif
-
+	 
 #ifndef BTRFS_IOC_CLONE_RANGE
 
 	struct btrfs_ioctl_clone_range_args {

include/crucible/cache.h

@@ -8,7 +8,6 @@
 #include <map>
 #include <mutex>
 #include <tuple>
-#include <vector>
 
 namespace crucible {
 	using namespace std;
@@ -18,7 +17,7 @@ namespace crucible {
 	public:
 		using Key = tuple<Arguments...>;
 		using Func = function<Return(Arguments...)>;
-		using Time = size_t;
+		using Time = unsigned;
 		using Value = pair<Time, Return>;
 	private:
 		Func		m_fn;
@@ -28,7 +27,7 @@ namespace crucible {
 		size_t		m_max_size;
 		mutex		m_mutex;
 
-		bool check_overflow();
+		void check_overflow();
 	public:
 		LRUCache(Func f = Func(), size_t max_size = 100);
 
@@ -52,24 +51,21 @@ namespace crucible {
 	}
 
 	template <class Return, class... Arguments>
-	bool
+	void
 	LRUCache<Return, Arguments...>::check_overflow()
 	{
-		if (m_map.size() <= m_max_size) {
-			return false;
-		}
-		vector<pair<Key, Time>> key_times;
-		key_times.reserve(m_map.size());
+		if (m_map.size() <= m_max_size) return;
+		vector<pair<Key, Time>> map_contents;
+		map_contents.reserve(m_map.size());
 		for (auto i : m_map) {
-			key_times.push_back(make_pair(i.first, i.second.first));
+			map_contents.push_back(make_pair(i.first, i.second.first));
 		}
-		sort(key_times.begin(), key_times.end(), [](const pair<Key, Time> &a, const pair<Key, Time> &b) {
+		sort(map_contents.begin(), map_contents.end(), [](const pair<Key, Time> &a, const pair<Key, Time> &b) {
 			return a.second < b.second;
 		});
-		for (size_t i = 0; i < key_times.size() / 2; ++i) {
-			m_map.erase(key_times[i].first);
+		for (size_t i = 0; i < map_contents.size() / 2; ++i) {
+			m_map.erase(map_contents[i].first);
 		}
-		return true;
 	}
 
 	template <class Return, class... Arguments>
@@ -124,7 +120,7 @@ namespace crucible {
 		if (found == m_map.end()) {
 			// No, release cache lock and acquire key lock
 			lock.unlock();
-			auto key_lock = m_lockset.make_lock(k);
+			typename LockSet<Key>::Lock key_lock(m_lockset, k);
 
 			// Did item appear in cache while we were waiting for key?
 			lock.lock();
@@ -144,14 +140,9 @@ namespace crucible {
 				// We hold a lock on this key so we are the ones to insert it
 				THROW_CHECK0(runtime_error, inserted);
 
-				// Release key lock, keep the cache lock
+				// Release key lock and clean out overflow
 				key_lock.unlock();
-
-				// Check to see if we have too many items and reduce if so.
-				if (check_overflow()) {
-					// Reset iterator
-					found = m_map.find(k);
-				}
+				check_overflow();
 			}
 		}
 
@@ -162,9 +153,7 @@ namespace crucible {
 		if (!inserted) {
 			found->second.first = m_ctr++;
 		}
-		// Make copy before releasing lock
-		auto rv = found->second.second;
-		return rv;
+		return found->second.second;
 	}
 
 	template<class Return, class... Arguments>
@@ -197,7 +186,7 @@ namespace crucible {
 		if (found == m_map.end()) {
 			// No, release cache lock and acquire key lock
 			lock.unlock();
-			auto key_lock = m_lockset.make_lock(k);
+			typename LockSet<Key>::Lock key_lock(m_lockset, k);
 
 			// Did item appear in cache while we were waiting for key?
 			lock.lock();
@@ -215,12 +204,7 @@ namespace crucible {
 
 				// Release key lock and clean out overflow
 				key_lock.unlock();
-
-				// Check to see if we have too many items and reduce if so.
-				if (check_overflow()) {
-					// Reset iterator
-					found = m_map.find(k);
-				}
+				check_overflow();
 			}
 		}
 

include/crucible/chatter.h

@@ -45,8 +45,6 @@ namespace crucible {
 		template <class T> Chatter &operator<<(const T& arg);
 
 		~Chatter();
-
-		static void enable_timestamp(bool prefix_timestamp);
 	};
 
 	template <class Argument>
@@ -88,6 +86,16 @@ namespace crucible {
 		}
 	};
 
+	template <>
+	struct ChatterTraits<ostream &> {
+		Chatter &
+		operator()(Chatter &c, ostream & arg)
+		{
+			c.get_os() << arg;
+			return c;
+		}
+	};
+
 	class ChatterBox {
 		string m_file;
 		int m_line;

include/crucible/cleanup.h

@@ -1,18 +0,0 @@
-#ifndef CRUCIBLE_CLEANUP_H
-#define CRUCIBLE_CLEANUP_H
-
-#include <functional>
-
-namespace crucible {
-	using namespace std;
-
-	class Cleanup {
-		function<void()> m_cleaner;
-	public:
-		Cleanup(function<void()> func);
-		~Cleanup();
-	};
-
-}
-
-#endif // CRUCIBLE_CLEANUP_H

include/crucible/crc64.h

@@ -3,11 +3,11 @@
 
 #include <cstdint>
 #include <cstdlib>
-#include <cstring>
 
 namespace crucible {
 	namespace Digest {
 		namespace CRC {
+			uint64_t crc64(const char *s);
 			uint64_t crc64(const void *p, size_t len);
 		};
 	};

include/crucible/error.h

@@ -100,6 +100,12 @@ namespace crucible {
 } while (0)
 
 // macros for checking a constraint
+#define CHECK_CONSTRAINT(value, expr) do { \
+	if (!(expr)) { \
+		THROW_ERROR(out_of_range, #value << " = " << value << " failed constraint check (" << #expr << ")"); \
+	} \
+} while(0)
+
 #define THROW_CHECK0(type, expr) do { \
 	if (!(expr)) { \
 		THROW_ERROR(type, "failed constraint check (" << #expr << ")"); \

include/crucible/execpipe.h

@@ -0,0 +1,28 @@
+#ifndef CRUCIBLE_EXECPIPE_H
+#define CRUCIBLE_EXECPIPE_H
+
+#include "crucible/fd.h"
+
+#include <functional>
+#include <limits>
+#include <string>
+
+namespace crucible {
+	using namespace std;
+
+	void redirect_stdin(const Fd &child_fd);
+	void redirect_stdin_stdout(const Fd &child_fd);
+	void redirect_stdin_stdout_stderr(const Fd &child_fd);
+	void redirect_stdout(const Fd &child_fd);
+	void redirect_stdout_stderr(const Fd &child_fd);
+
+	// Open a pipe (actually socketpair) to child process, then execute code in that process.
+	// e.g. popen([] () { system("echo Hello, World!"); });
+	// Forked process will exit when function returns.
+	Fd popen(function<int()> f, function<void(const Fd &child_fd)> import_fd_fn = redirect_stdin_stdout);
+
+	// Read all the data from fd into a string
+        string read_all(Fd fd, size_t max_bytes = numeric_limits<size_t>::max(), size_t chunk_bytes = 4096);
+};
+
+#endif // CRUCIBLE_EXECPIPE_H

include/crucible/extentwalker.h

@@ -8,15 +8,15 @@ namespace crucible {
 
 	// FIXME:  ExtentCursor is probably a better name
 	struct Extent {
-		off_t		m_begin = 0;
-		off_t		m_end = 0;
-		uint64_t	m_physical = 0;
-		uint64_t	m_flags = 0;
+		off_t		m_begin;
+		off_t		m_end;
+		uint64_t	m_physical;
+		uint64_t	m_flags;
 
 		// Btrfs extent reference details
-		off_t		m_physical_len = 0;
-		off_t		m_logical_len = 0;
-		off_t		m_offset = 0;
+		off_t		m_physical_len;
+		off_t		m_logical_len;
+		off_t		m_offset;
 
 		// fiemap flags are uint32_t, so bits 32..63 are OK for us
 
@@ -38,12 +38,10 @@ namespace crucible {
 		off_t physical_len() const { return m_physical_len; }
 		off_t logical_len() const { return m_logical_len; }
 		off_t offset() const { return m_offset; }
-		bool compressed() const;
-		uint64_t bytenr() const;
 		bool operator==(const Extent &that) const;
 		bool operator!=(const Extent &that) const { return !(*this == that); }
 
-		Extent() = default;
+		Extent();
 		Extent(const Extent &e) = default;
 	};
 

include/crucible/fd.h

@@ -13,10 +13,6 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 
-// ioctl
-#include <sys/ioctl.h>
-#include <linux/fs.h>
-
 // socket
 #include <sys/socket.h>
 
@@ -57,10 +53,6 @@ namespace crucible {
 
         typedef ResourceHandle<int, IOHandle> Fd;
 
-	static string __relative_path;
-	void set_relative_path(string path);
-	string relative_path();
-
 	// Functions named "foo_or_die" throw exceptions on failure.
 
 	// Attempt to open the file with the given mode
@@ -78,11 +70,10 @@ namespace crucible {
 	string mmap_flags_ntoa(int flags);
 
 	// Unlink, rename
+	void unlink_or_die(const string &file);
 	void rename_or_die(const string &from, const string &to);
 	void renameat_or_die(int fromfd, const string &frompath, int tofd, const string &topath);
 
-	void ftruncate_or_die(int fd, off_t size);
-
 	// Read or write structs:
 	// There is a template specialization to read or write strings
 	// Three-arg version of read_or_die/write_or_die throws an error on incomplete read/writes
@@ -129,9 +120,6 @@ namespace crucible {
 	template<> void pread_or_die<string>(int fd, string& str, off_t offset);
 	template<> void pread_or_die<vector<char>>(int fd, vector<char>& str, off_t offset);
 	template<> void pread_or_die<vector<uint8_t>>(int fd, vector<uint8_t>& str, off_t offset);
-	template<> void pwrite_or_die<string>(int fd, const string& str, off_t offset);
-	template<> void pwrite_or_die<vector<char>>(int fd, const vector<char>& str, off_t offset);
-	template<> void pwrite_or_die<vector<uint8_t>>(int fd, const vector<uint8_t>& str, off_t offset);
 
 	// A different approach to reading a simple string
 	string read_string(int fd, size_t size);
@@ -149,9 +137,6 @@ namespace crucible {
 		Stat &lstat(const string &filename);
 	};
 
-	int ioctl_iflags_get(int fd);
-	void ioctl_iflags_set(int fd, int attr);
-
 	string st_mode_ntoa(mode_t mode);
 
 	// Because it's not trivial to do correctly

include/crucible/fs.h

@@ -13,7 +13,6 @@
 
 #include <cstdint>
 #include <iosfwd>
-#include <set>
 #include <vector>
 
 #include <fcntl.h>
@@ -112,8 +111,8 @@ namespace crucible {
 		BTRFS_COMPRESS_NONE  = 0,
 		BTRFS_COMPRESS_ZLIB  = 1,
 		BTRFS_COMPRESS_LZO   = 2,
-		BTRFS_COMPRESS_ZSTD  = 3,
-		BTRFS_COMPRESS_TYPES = 3
+		BTRFS_COMPRESS_TYPES = 2,
+		BTRFS_COMPRESS_LAST  = 3,
 	} btrfs_compression_type;
 
 	struct FiemapExtent : public fiemap_extent {
@@ -151,14 +150,13 @@ namespace crucible {
 		BtrfsIoctlSearchHeader();
 		vector<char> m_data;
 		size_t set_data(const vector<char> &v, size_t offset);
-		bool operator<(const BtrfsIoctlSearchHeader &that) const;
 	};
 
 	ostream & operator<<(ostream &os, const btrfs_ioctl_search_header &hdr);
 	ostream & operator<<(ostream &os, const BtrfsIoctlSearchHeader &hdr);
 
 	struct BtrfsIoctlSearchKey : public btrfs_ioctl_search_key {
-		BtrfsIoctlSearchKey(size_t buf_size = 4096);
+		BtrfsIoctlSearchKey(size_t buf_size = 1024 * 1024);
 		virtual bool do_ioctl_nothrow(int fd);
 		virtual void do_ioctl(int fd);
 
@@ -166,15 +164,14 @@ namespace crucible {
 		void next_min(const BtrfsIoctlSearchHeader& ref);
 
 		size_t m_buf_size;
-		set<BtrfsIoctlSearchHeader> m_result;
-
+		vector<BtrfsIoctlSearchHeader> m_result;
 	};
 
 	ostream & operator<<(ostream &os, const btrfs_ioctl_search_key &key);
 	ostream & operator<<(ostream &os, const BtrfsIoctlSearchKey &key);
 
 	string btrfs_search_type_ntoa(unsigned type);
-	string btrfs_search_objectid_ntoa(uint64_t objectid);
+	string btrfs_search_objectid_ntoa(unsigned objectid);
 
 	uint64_t btrfs_get_root_id(int fd);
 	uint64_t btrfs_get_root_transid(int fd);

include/crucible/interp.h

@@ -0,0 +1,106 @@
+#ifndef CRUCIBLE_INTERP_H
+#define CRUCIBLE_INTERP_H
+
+#include "crucible/error.h"
+
+#include <map>
+#include <memory>
+#include <string>
+#include <vector>
+
+namespace crucible {
+	using namespace std;
+
+	struct ArgList : public vector<string> {
+		ArgList(const char **argv);
+		// using vector<string>::vector ... doesn't work:
+		// error: ‘std::vector<std::basic_string<char> >::vector’ names constructor
+		// Still doesn't work in 4.9 because it can't manage a conversion
+		ArgList(const vector<string> &&that);
+	};
+
+	struct ArgActor {
+		struct ArgActorBase {
+			virtual void predicate(void *obj, string arg);
+		};
+
+		template <class T>
+		struct ArgActorDerived {
+			function<void(T, string)> m_func;
+
+			ArgActorDerived(decltype(m_func) func) :
+				m_func(func)
+			{
+			}
+
+			void predicate(void *obj, string arg) override
+			{
+				T &op = *(reinterpret_cast<T*>(obj));
+				m_func(op, obj);
+			}
+		};
+
+		template <class T>
+		ArgActor(T, function<void(T, string)> func) :
+			m_actor(make_shared(ArgActorDerived<T>(func)))
+		{
+		}
+
+		ArgActor() = default;
+
+		void predicate(void *t, string arg)
+		{
+			if (m_actor) {
+				m_actor->predicate(t, arg);
+			} else {
+				THROW_ERROR(invalid_argument, "null m_actor for predicate arg '" << arg << "'");
+			}
+		}
+
+	private:
+		shared_ptr<ArgActorBase> m_actor;
+	};
+
+	struct ArgParser {
+		~ArgParser();
+		ArgParser();
+
+		void add_opt(string opt, ArgActor actor);
+
+		template <class T>
+		void
+		parse(T t, const ArgList &args)
+		{
+			void *vt = &t;
+			parse_backend(vt, args);
+		}
+		
+	private:
+		void parse_backend(void *t, const ArgList &args);
+		map<string, ArgActor>	m_string_opts;
+	};
+
+	struct Command {
+		virtual ~Command();
+		virtual int exec(const ArgList &args) = 0;
+	};
+
+	struct Proc : public Command {
+		int exec(const ArgList &args) override;
+		Proc(const function<int(const ArgList &)> &f);
+	private:
+		function<int(const ArgList &)> m_cmd;
+	};
+
+	struct Interp {
+		virtual ~Interp();
+		Interp(const map<string, shared_ptr<Command> > &cmdlist);
+		void add_command(const string &name, const shared_ptr<Command> &command);
+		int exec(const ArgList &args);
+	private:
+		Interp(const Interp &) = delete;
+		map<string, shared_ptr<Command> > m_commands;
+	};
+
+};
+#endif // CRUCIBLE_INTERP_H

include/crucible/lockset.h

@@ -1,20 +1,14 @@
 #ifndef CRUCIBLE_LOCKSET_H
 #define CRUCIBLE_LOCKSET_H
 
-#include <crucible/cleanup.h>
 #include <crucible/error.h>
-#include <crucible/process.h>
 
 #include <cassert>
 
 #include <condition_variable>
 #include <iostream>
-#include <limits>
-#include <map>
-#include <memory>
 #include <mutex>
 #include <set>
-#include <thread>
 
 namespace crucible {
 	using namespace std;
@@ -23,39 +17,14 @@ namespace crucible {
 	class LockSet {
 
 	public:
-		using set_type = map<T, pid_t>;
-		using key_type = typename set_type::key_type;
+		using key_type = T;
+		using set_type = set<T>;
 
 	private:
 
 		set_type			m_set;
 		mutex				m_mutex;
 		condition_variable		m_condvar;
-		size_t				m_max_size = numeric_limits<size_t>::max();
-		set<uint64_t>			m_priorities;
-		uint64_t			m_priority_counter;
-
-		bool full();
-		bool first_in_priority(uint64_t my_priority);
-		bool locked(const key_type &name);
-
-		class Lock {
-			LockSet		&m_lockset;
-			key_type	m_name;
-			bool		m_locked;
-
-			Lock() = delete;
-			Lock(const Lock &) = delete;
-			Lock& operator=(const Lock &) = delete;
-			Lock(Lock &&that) = delete;
-			Lock& operator=(Lock &&that) = delete;
-		public:
-			~Lock();
-			Lock(LockSet &lockset, const key_type &name, bool start_locked = true);
-			void lock();
-			void unlock();
-			bool try_lock();
-		};
 
 	public:
 		~LockSet();
@@ -67,21 +36,26 @@ namespace crucible {
 		size_t size();
 		bool empty();
 		set_type copy();
+		void wait_unlock(double interval);
 
-		void max_size(size_t max);
-
-		class LockHandle {
-			shared_ptr<Lock> m_lock;
+		class Lock {
+			LockSet		&m_lockset;
+			key_type	m_name;
+			bool		m_locked;
 
+			Lock() = delete;
+			Lock(const Lock &) = delete;
+			Lock& operator=(const Lock &) = delete;
 		public:
-			LockHandle(LockSet &lockset, const key_type &name, bool start_locked = true) :
-				m_lock(make_shared<Lock>(lockset, name, start_locked)) {}
-			void lock() { m_lock->lock(); }
-			void unlock() { m_lock->unlock(); }
-			bool try_lock() { return m_lock->try_lock(); }
+			~Lock();
+			Lock(LockSet &lockset, const key_type &m_name, bool start_locked = true);
+			Lock(Lock &&that);
+			Lock& operator=(Lock &&that);
+			void lock();
+			void unlock();
+			bool try_lock();
 		};
 
-		LockHandle make_lock(const key_type &name, bool start_locked = true);
 	};
 
 	template <class T>
@@ -94,65 +68,16 @@ namespace crucible {
 		assert(m_set.empty());
 	}
 
-	template <class T>
-	bool
-	LockSet<T>::full()
-	{
-		return m_set.size() >= m_max_size;
-	}
-
-	template <class T>
-	bool
-	LockSet<T>::first_in_priority(uint64_t my_priority)
-	{
-#if 1
-		auto counter = m_max_size;
-		for (auto i : m_priorities) {
-			if (i == my_priority) {
-				return true;
-			}
-			if (++counter > m_max_size) {
-				return false;
-			}
-		}
-		THROW_ERROR(runtime_error, "my_priority " << my_priority << " not in m_priorities (size " << m_priorities.size() << ")");
-#else
-		return *m_priorities.begin() == my_priority;
-#endif
-	}
-
-	template <class T>
-	bool
-	LockSet<T>::locked(const key_type &name)
-	{
-		return m_set.count(name);
-	}
-
-	template <class T>
-	void
-	LockSet<T>::max_size(size_t new_max_size)
-	{
-		THROW_CHECK1(out_of_range, new_max_size, new_max_size > 0);
-		m_max_size = new_max_size;
-	}
-
 	template <class T>
 	void
 	LockSet<T>::lock(const key_type &name)
 	{
 		unique_lock<mutex> lock(m_mutex);
-		auto my_priority = m_priority_counter++;
-		Cleanup cleanup([&]() {
-			m_priorities.erase(my_priority);
-		});
-		m_priorities.insert(my_priority);
-		while (full() || locked(name) || !first_in_priority(my_priority)) {
+		while (m_set.count(name)) {
 			m_condvar.wait(lock);
 		}
-		auto rv = m_set.insert(make_pair(name, gettid()));
+		auto rv = m_set.insert(name);
 		THROW_CHECK0(runtime_error, rv.second);
-		// We removed our priority slot so other threads have to check again
-		m_condvar.notify_all();
 	}
 
 	template <class T>
@@ -160,10 +85,10 @@ namespace crucible {
 	LockSet<T>::try_lock(const key_type &name)
 	{
 		unique_lock<mutex> lock(m_mutex);
-		if (full() || locked(name)) {
+		if (m_set.count(name)) {
 			return false;
 		}
-		auto rv = m_set.insert(make_pair(name, gettid()));
+		auto rv = m_set.insert(name);
 		THROW_CHECK1(runtime_error, name, rv.second);
 		return true;
 	}
@@ -173,13 +98,20 @@ namespace crucible {
 	LockSet<T>::unlock(const key_type &name)
 	{
 		unique_lock<mutex> lock(m_mutex);
-		auto erase_count = m_set.erase(name);
 		m_condvar.notify_all();
-		lock.unlock();
-		this_thread::yield();
+		auto erase_count = m_set.erase(name);
 		THROW_CHECK1(invalid_argument, erase_count, erase_count == 1);
 	}
 
+	template <class T>
+	void
+	LockSet<T>::wait_unlock(double interval)
+	{
+		unique_lock<mutex> lock(m_mutex);
+		if (m_set.empty()) return;
+		m_condvar.wait_for(lock, chrono::duration<double>(interval));
+	}
+
 	template <class T>
 	size_t
 	LockSet<T>::size()
@@ -201,10 +133,7 @@ namespace crucible {
 	LockSet<T>::copy()
 	{
 		unique_lock<mutex> lock(m_mutex);
-		// Make temporary copy of set while protected by mutex
-		auto rv = m_set;
-		// Return temporary copy after releasing lock
-		return rv;
+		return m_set;
 	}
 
 	template <class T>
@@ -254,10 +183,26 @@ namespace crucible {
 	}
 
 	template <class T>
-	typename LockSet<T>::LockHandle
-	LockSet<T>::make_lock(const key_type &name, bool start_locked)
+	LockSet<T>::Lock::Lock(Lock &&that) :
+		m_lockset(that.lockset),
+		m_name(that.m_name),
+		m_locked(that.m_locked)
 	{
-		return LockHandle(*this, name, start_locked);
+		that.m_locked = false;
+	}
+
+	template <class T>
+	typename LockSet<T>::Lock &
+	LockSet<T>::Lock::operator=(Lock &&that)
+	{
+		THROW_CHECK2(invalid_argument, &m_lockset, &that.m_lockset, &m_lockset == &that.m_lockset);
+		if (m_locked && that.m_name != m_name) {
+			unlock();
+		}
+		m_name = that.m_name;
+		m_locked = that.m_locked;
+		that.m_locked = false;
+		return *this;
 	}
 
 }

include/crucible/ntoa.h

@@ -7,12 +7,12 @@ namespace crucible {
 	using namespace std;
 
 	struct bits_ntoa_table {
-		unsigned long long n;
-		unsigned long long mask;
+		unsigned long n;
+		unsigned long mask;
 		const char *a;
 	};
 
-	string bits_ntoa(unsigned long long n, const bits_ntoa_table *a);
+	string bits_ntoa(unsigned long n, const bits_ntoa_table *a);
 
 };
 

include/crucible/resource.h

@@ -8,7 +8,6 @@
 #include <memory>
 #include <mutex>
 #include <iostream>
-#include <stdexcept>
 
 namespace crucible {
 	using namespace std;
@@ -45,29 +44,36 @@ namespace crucible {
 
 	private:
 		using traits_type = ResourceTraits<Key, Resource>;
-		using weak_ptr_type = weak_ptr<Resource>;
-		using map_type = map<key_type, weak_ptr_type>;
+
+		class ResourceHolder {
+			resource_ptr_type m_ptr;
+		public:
+			~ResourceHolder();
+			ResourceHolder(resource_ptr_type that);
+			ResourceHolder(const ResourceHolder &that) = default;
+			ResourceHolder(ResourceHolder &&that) = default;
+			ResourceHolder& operator=(ResourceHolder &&that) = default;
+			ResourceHolder& operator=(const ResourceHolder &that) = default;
+			resource_ptr_type get_resource_ptr() const;
+		};
+
+		using holder_ptr_type = shared_ptr<ResourceHolder>;
+		using weak_holder_ptr_type = weak_ptr<ResourceHolder>;
+		using map_type = map<key_type, weak_holder_ptr_type>;
 
 		// The only instance variable
-		resource_ptr_type m_ptr;
+		holder_ptr_type m_ptr;
 
 		// A bunch of static variables and functions
-		static mutex s_map_mutex;
-		static map_type s_map;
-		static resource_ptr_type insert(const key_type &key);
-		static resource_ptr_type insert(const resource_ptr_type &res);
-		static void clean_locked();
+		static mutex &s_mutex();
+		static shared_ptr<map_type> s_map();
+		static holder_ptr_type insert(const key_type &key);
+		static holder_ptr_type insert(const resource_ptr_type &res);
+		static void erase(const key_type &key);
 		static ResourceTraits<Key, Resource> s_traits;
 
 	public:
 
-		// Exceptions
-		struct duplicate_resource : public invalid_argument {
-			key_type m_key;
-			key_type get_key() const;
-			duplicate_resource(const key_type &key);
-		};
-
 		// test for resource.  A separate operator because key_type could be confused with bool.
 		bool operator!() const;
 
@@ -83,15 +89,8 @@ namespace crucible {
 		ResourceHandle(const resource_ptr_type &res);
 		ResourceHandle& operator=(const resource_ptr_type &res);
 
-		// default construct/assign/move is public and mostly harmless
+		// default constructor is public
 		ResourceHandle() = default;
-		ResourceHandle(const ResourceHandle &that) = default;
-		ResourceHandle(ResourceHandle &&that) = default;
-		ResourceHandle& operator=(const ResourceHandle &that) = default;
-		ResourceHandle& operator=(ResourceHandle &&that) = default;
-
-		// Nontrivial destructor
-		~ResourceHandle();
 
 		// forward anything else to the Resource constructor
 		// if we can do so unambiguously
@@ -110,7 +109,7 @@ namespace crucible {
 
 		// get pointer to Resource object (nothrow, result may be null)
 		resource_ptr_type get_resource_ptr() const;
-		// this version throws
+		// this version throws and is probably not thread safe
 		resource_ptr_type operator->() const;
 
 		// dynamic casting of the resource (throws if cast fails)
@@ -146,94 +145,139 @@ namespace crucible {
 	}
 
 	template <class Key, class Resource>
-	ResourceHandle<Key, Resource>::duplicate_resource::duplicate_resource(const key_type &key) :
-		invalid_argument("duplicate resource"),
-		m_key(key)
+	ResourceHandle<Key, Resource>::ResourceHolder::ResourceHolder(resource_ptr_type that) :
+		m_ptr(that)
 	{
+		// Cannot insert ourselves here since our shared_ptr does not exist yet.
 	}
 
 	template <class Key, class Resource>
-	auto
-	ResourceHandle<Key, Resource>::duplicate_resource::get_key() const -> key_type
+	mutex &
+	ResourceHandle<Key, Resource>::s_mutex()
 	{
-		return m_key;
+		static mutex gcc_won_t_instantiate_this_either;
+		return gcc_won_t_instantiate_this_either;
+	}
+
+	template <class Key, class Resource>
+	shared_ptr<typename ResourceHandle<Key, Resource>::map_type>
+	ResourceHandle<Key, Resource>::s_map()
+	{
+		static shared_ptr<map_type> gcc_won_t_instantiate_the_damn_static_vars;
+		if (!gcc_won_t_instantiate_the_damn_static_vars) {
+			gcc_won_t_instantiate_the_damn_static_vars = make_shared<map_type>();
+		}
+		return gcc_won_t_instantiate_the_damn_static_vars;
 	}
 
 	template <class Key, class Resource>
 	void
-	ResourceHandle<Key, Resource>::clean_locked()
+	ResourceHandle<Key, Resource>::erase(const key_type &key)
 	{
-		// Must be called with lock held
-		for (auto i = s_map.begin(); i != s_map.end(); ) {
-			auto this_i = i;
-			++i;
-			if (this_i->second.expired()) {
-				s_map.erase(this_i);
+		unique_lock<mutex> lock(s_mutex());
+		// Resources are allowed to set their Keys to null.
+		if (s_traits.is_null_key(key)) {
+			// Clean out any dead weak_ptr objects.
+			for (auto i = s_map()->begin(); i != s_map()->end(); ) {
+				if (! (*i).second.lock()) {
+					i = s_map()->erase(i);
+				} else {
+					++i;
+				}
 			}
+			return;
+		}
+		auto erased = s_map()->erase(key);
+		if (erased != 1) {
+			cerr << __PRETTY_FUNCTION__ << ": WARNING: s_map()->erase(" << key << ") returned " << erased << " != 1" << endl;
 		}
 	}
 
 	template <class Key, class Resource>
-	typename ResourceHandle<Key, Resource>::resource_ptr_type
+	ResourceHandle<Key, Resource>::ResourceHolder::~ResourceHolder()
+	{
+		if (!m_ptr) {
+			// Probably something harmless like a failed constructor.
+			cerr << __PRETTY_FUNCTION__ << ": WARNING: destroying null m_ptr" << endl;
+			return;
+		}
+		Key key = s_traits.get_key(*m_ptr);
+		ResourceHandle::erase(key);
+	}
+
+	template <class Key, class Resource>
+	typename ResourceHandle<Key, Resource>::holder_ptr_type
 	ResourceHandle<Key, Resource>::insert(const key_type &key)
 	{
 		// no Resources for null keys
 		if (s_traits.is_null_key(key)) {
-			return resource_ptr_type();
+			return holder_ptr_type();
 		}
-		unique_lock<mutex> lock(s_map_mutex);
-		auto found = s_map.find(key);
-		if (found != s_map.end()) {
-			resource_ptr_type rv = found->second.lock();
+		unique_lock<mutex> lock(s_mutex());
+		// find ResourceHolder for non-null key
+		auto found = s_map()->find(key);
+		if (found != s_map()->end()) {
+			holder_ptr_type rv = (*found).second.lock();
+			// a weak_ptr may have expired
 			if (rv) {
-				// Use existing Resource
 				return rv;
-			} else {
-				// It's OK for the map to temporarily contain an expired weak_ptr to some dead Resource
-				clean_locked();
 			}
 		}
 		// not found or expired, throw any existing ref away and make a new one
 		resource_ptr_type rpt = s_traits.make_resource(key);
+		holder_ptr_type hpt = make_shared<ResourceHolder>(rpt);
 		// store weak_ptr in map
-		s_map[key] = rpt;
+		(*s_map())[key] = hpt;
 		// return shared_ptr
-		return rpt;
+		return hpt;
 	};
 
 	template <class Key, class Resource>
-	typename ResourceHandle<Key, Resource>::resource_ptr_type
+	typename ResourceHandle<Key, Resource>::holder_ptr_type
 	ResourceHandle<Key, Resource>::insert(const resource_ptr_type &res)
 	{
-		// no Resources for null keys
+		// no Resource, no ResourceHolder.
 		if (!res) {
-			return resource_ptr_type();
+			return holder_ptr_type();
 		}
+		// no ResourceHolders for null keys either.
 		key_type key = s_traits.get_key(*res);
 		if (s_traits.is_null_key(key)) {
-			return resource_ptr_type();
+			return holder_ptr_type();
 		}
-		unique_lock<mutex> lock(s_map_mutex);
-		// find Resource for non-null key
-		auto found = s_map.find(key);
-		if (found != s_map.end()) {
-			resource_ptr_type rv = found->second.lock();
-			// It's OK for the map to temporarily contain an expired weak_ptr to some dead Resource...
+		unique_lock<mutex> lock(s_mutex());
+		// find ResourceHolder for non-null key
+		auto found = s_map()->find(key);
+		if (found != s_map()->end()) {
+			holder_ptr_type rv = (*found).second.lock();
+			// The map doesn't own the ResourceHolders, the ResourceHandles do.
+			// It's OK for the map to contain an expired weak_ptr to some dead ResourceHolder...
 			if (rv) {
-				// ...but not a duplicate Resource.
-				if (rv.owner_before(res) || res.owner_before(rv)) {
-					throw duplicate_resource(key);
+				// found ResourceHolder, look at pointer
+				resource_ptr_type rp = rv->get_resource_ptr();
+				// We do not store references to null Resources.
+				assert(rp);
+				// Key retrieved for an existing object must match key searched or be null.
+				key_type found_key = s_traits.get_key(*rp);
+				bool found_key_is_null = s_traits.is_null_key(found_key);
+				assert(found_key_is_null || found_key == key);
+				if (!found_key_is_null) {
+					// We do not store references to duplicate resources.
+					if (rp.owner_before(res) || res.owner_before(rp)) {
+						cerr << "inserting new Resource with existing Key " << key << " not allowed at " << __PRETTY_FUNCTION__ << endl;;
+						abort();
+						// THROW_ERROR(out_of_range, "inserting new Resource with existing Key " << key << " not allowed at " << __PRETTY_FUNCTION__);
+					}
+					// rv is good, return it
+					return rv;
 				}
-				// Use the existing Resource (discard the caller's).
-				return rv;
-			} else {
-				// Clean out expired weak_ptrs
-				clean_locked();
 			}
 		}
-		// not found or expired, make a new one or replace old one
-		s_map[key] = res;
-		return res;
+		// not found or expired, make a new one
+		holder_ptr_type rv = make_shared<ResourceHolder>(res);
+		s_map()->insert(make_pair(key, weak_holder_ptr_type(rv)));
+		// no need to check s_map result, we are either replacing a dead weak_ptr or adding a new one
+		return rv;
 	};
 
 	template <class Key, class Resource>
@@ -265,47 +309,31 @@ namespace crucible {
 	}
 
 	template <class Key, class Resource>
-	ResourceHandle<Key, Resource>::~ResourceHandle()
+	typename ResourceHandle<Key, Resource>::resource_ptr_type
+	ResourceHandle<Key, Resource>::ResourceHolder::get_resource_ptr() const
 	{
-		// No pointer, nothing to do
-		if (!m_ptr) {
-			return;
-		}
-		// Save key so we can clean the map
-		auto key = s_traits.get_key(*m_ptr);
-		// Save a weak_ptr so we can tell if we need to clean the map
-		weak_ptr_type wp = m_ptr;
-		// Drop shared_ptr
-		m_ptr.reset();
-		// If there are still other references to the shared_ptr, we can stop now
-		if (!wp.expired()) {
-			return;
-		}
-		// Remove weak_ptr from map if it has expired
-		// (and not been replaced in the meantime)
-		unique_lock<mutex> lock_map(s_map_mutex);
-		auto found = s_map.find(key);
-		// Map entry may have been replaced, so check for expiry again
-		if (found != s_map.end() && found->second.expired()) {
-			s_map.erase(key);
-		}
+		return m_ptr;
 	}
 
 	template <class Key, class Resource>
 	typename ResourceHandle<Key, Resource>::resource_ptr_type
 	ResourceHandle<Key, Resource>::get_resource_ptr() const
 	{
-		return m_ptr;
+		if (!m_ptr) {
+			return resource_ptr_type();
+		}
+		return m_ptr->get_resource_ptr();
 	}
 
 	template <class Key, class Resource>
 	typename ResourceHandle<Key, Resource>::resource_ptr_type
 	ResourceHandle<Key, Resource>::operator->() const
 	{
-		if (!m_ptr) {
+		resource_ptr_type rp = get_resource_ptr();
+		if (!rp) {
 			THROW_ERROR(out_of_range, __PRETTY_FUNCTION__ << " called on null Resource");
 		}
-		return m_ptr;
+		return rp;
 	}
 
 	template <class Key, class Resource>
@@ -314,10 +342,11 @@ namespace crucible {
 	ResourceHandle<Key, Resource>::cast() const
 	{
 		shared_ptr<T> dp;
-		if (!m_ptr) {
+		resource_ptr_type rp = get_resource_ptr();
+		if (!rp) {
 			return dp;
 		}
-		dp = dynamic_pointer_cast<T>(m_ptr);
+		dp = dynamic_pointer_cast<T>(rp);
 		if (!dp) {
 			throw bad_cast();
 		}
@@ -328,10 +357,11 @@ namespace crucible {
 	typename ResourceHandle<Key, Resource>::key_type
 	ResourceHandle<Key, Resource>::get_key() const
 	{
-		if (!m_ptr) {
+		resource_ptr_type rp = get_resource_ptr();
+		if (!rp) {
 			return s_traits.get_null_key();
 		} else {
-			return s_traits.get_key(*m_ptr);
+			return s_traits.get_key(*rp);
 		}
 	}
 
@@ -348,15 +378,9 @@ namespace crucible {
 		return s_traits.is_null_key(operator key_type());
 	}
 
-	// Apparently GCC wants these to be used before they are defined.
 	template <class Key, class Resource>
 	ResourceTraits<Key, Resource> ResourceHandle<Key, Resource>::s_traits;
 
-	template <class Key, class Resource>
-	mutex ResourceHandle<Key, Resource>::s_map_mutex;
-
-	template <class Key, class Resource>
-	typename ResourceHandle<Key, Resource>::map_type ResourceHandle<Key, Resource>::s_map;
 
 }
 

include/crucible/time.h

@@ -32,11 +32,10 @@ namespace crucible {
 		Timer	m_timer;
 		double	m_rate;
 		double	m_burst;
-		double  m_tokens = 0.0;
+		double  m_tokens;
 		mutex	m_mutex;
 
 		void update_tokens();
-		RateLimiter() = delete;
 	public:
 		RateLimiter(double rate, double burst);
 		RateLimiter(double rate);

include/crucible/timequeue.h

@@ -23,7 +23,7 @@ namespace crucible {
 	private:
 		struct Item {
 			Timestamp m_time;
-			unsigned long m_id;
+			unsigned m_id;
 			Task m_task;
 
 			bool operator<(const Item &that) const {
@@ -77,7 +77,7 @@ namespace crucible {
 	void
 	TimeQueue<Task>::push(const Task &task, double delay)
 	{
-		Timestamp time = chrono::high_resolution_clock::now() +
+		Timestamp time = chrono::high_resolution_clock::now() + 
 			chrono::duration_cast<chrono::high_resolution_clock::duration>(chrono::duration<double>(delay));
 		unique_lock<mutex> lock(m_mutex);
 		while (m_set.size() > m_max_queue_depth) {
@@ -91,7 +91,7 @@ namespace crucible {
 	void
 	TimeQueue<Task>::push_nowait(const Task &task, double delay)
 	{
-		Timestamp time = chrono::high_resolution_clock::now() +
+		Timestamp time = chrono::high_resolution_clock::now() + 
 			chrono::duration_cast<chrono::high_resolution_clock::duration>(chrono::duration<double>(delay));
 		unique_lock<mutex> lock(m_mutex);
 		m_set.insert(Item(time, task));

include/crucible/version.h

@@ -1,8 +0,0 @@
-#ifndef CRUCIBLE_VERSION_H
-#define CRUCIBLE_VERSION_H
-
-namespace crucible {
-	extern const char *VERSION;
-}
-
-#endif CRUCIBLE_VERSION_H

include/crucible/workqueue.h

@@ -124,9 +124,7 @@ namespace crucible {
 		if (m_set.empty()) {
 			return key_type();
 		} else {
-			// Make copy with lock held
-			auto rv = *m_set.begin();
-			return rv;
+			return *m_set.begin();
 		}
 	}
 
@@ -151,8 +149,7 @@ namespace crucible {
 	WorkQueue<Task>::copy()
 	{
 		unique_lock<mutex> lock(m_mutex);
-		auto rv = m_set;
-		return rv;
+		return m_set;
 	}
 
 	template <class Task>

lib/.gitignore

@@ -1 +0,0 @@
-.version.*

lib/Makefile

@@ -1,37 +1,37 @@
-TAG := $(shell git describe --always --dirty || echo UNKNOWN)
-
 default: libcrucible.so
 
 OBJS = \
-	chatter.o \
-	cleanup.o \
 	crc64.o \
+	chatter.o \
 	error.o \
+	execpipe.o \
 	extentwalker.o \
 	fd.o \
 	fs.o \
+	interp.o \
 	ntoa.o \
 	path.o \
 	process.o \
 	string.o \
 	time.o \
 	uuid.o \
-	.version.o \
 
 include ../makeflags
 
-depends.mk: *.cc
+LDFLAGS = -shared -luuid
+
+depends.mk: *.c *.cc
+	for x in *.c; do $(CC) $(CFLAGS) -M "$$x"; done > depends.mk.new
 	for x in *.cc; do $(CXX) $(CXXFLAGS) -M "$$x"; done >> depends.mk.new
 	mv -fv depends.mk.new depends.mk
 
-.version.cc: Makefile ../makeflags *.cc ../include/crucible/*.h
-	echo "namespace crucible { const char *VERSION = \"$(TAG)\"; }" > .version.new.cc
-	mv -f .version.new.cc .version.cc
-
 -include depends.mk
 
+%.o: %.c
+	$(CC) $(CFLAGS) -o $@ -c $<
+
 %.o: %.cc ../include/crucible/%.h
-	$(CXX) $(CXXFLAGS) -fPIC -o $@ -c $<
+	$(CXX) $(CXXFLAGS) -o $@ -c $<
 
 libcrucible.so: $(OBJS) Makefile
-	$(CXX) $(LDFLAGS) -fPIC -o $@ $(OBJS) -shared -Wl,-soname,$@ -luuid
+	$(CXX) $(LDFLAGS) -o $@ $(OBJS)

lib/chatter.cc

@@ -15,9 +15,8 @@
 namespace crucible {
 	using namespace std;
 
-	static shared_ptr<set<string>> chatter_names;
+	static auto_ptr<set<string>> chatter_names;
 	static const char *SPACETAB = " \t";
-	static bool add_prefix_timestamp = true;
 
 	static
 	void
@@ -49,31 +48,20 @@ namespace crucible {
 	{
 	}
 
-	void
-	Chatter::enable_timestamp(bool prefix_timestamp)
-	{
-		add_prefix_timestamp = prefix_timestamp;
-	}
-
 	Chatter::~Chatter()
 	{
 		ostringstream header_stream;
 
-		if (add_prefix_timestamp) {
-			time_t ltime;
-			DIE_IF_MINUS_ONE(time(&ltime));
-			struct tm ltm;
-			DIE_IF_ZERO(localtime_r(&ltime, &ltm));
+		time_t ltime;
+		DIE_IF_MINUS_ONE(time(&ltime));
+		struct tm ltm;
+		DIE_IF_ZERO(localtime_r(&ltime, &ltm));
 
-			char buf[1024];
-			DIE_IF_ZERO(strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", &ltm));
-
-			header_stream << buf;
-			header_stream << " " << getpid() << "." << gettid();
-		} else {
-			header_stream << "tid " << gettid();
-		}
+		char buf[1024];
+		DIE_IF_ZERO(strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", &ltm));
 
+		header_stream << buf;
+		header_stream << " " << getpid() << "." << gettid();
 		if (!m_name.empty()) {
 			header_stream << " " << m_name;
 		}

lib/cleanup.cc

@@ -1,17 +0,0 @@
-#include <crucible/cleanup.h>
-
-namespace crucible {
-
-	Cleanup::Cleanup(function<void()> func) :
-		m_cleaner(func)
-	{
-	}
-
-	Cleanup::~Cleanup()
-	{
-		if (m_cleaner) {
-			m_cleaner();
-		}
-	}
-
-}

lib/crc64.cc

@@ -1,31 +1,3 @@
-/* crc64.c -- compute CRC-64
- * Copyright (C) 2013 Mark Adler
- * Version 1.4  16 Dec 2013  Mark Adler
- */
-
-/*
- This software is provided 'as-is', without any express or implied
- warranty.  In no event will the author be held liable for any damages
- arising from the use of this software.
-
- Permission is granted to anyone to use this software for any purpose,
- including commercial applications, and to alter it and redistribute it
- freely, subject to the following restrictions:
-
- 1. The origin of this software must not be misrepresented; you must not
- claim that you wrote the original software. If you use this software
- in a product, an acknowledgment in the product documentation would be
- appreciated but is not required.
- 2. Altered source versions must be plainly marked as such, and must not be
- misrepresented as being the original software.
- 3. This notice may not be removed or altered from any source distribution.
-
- Mark Adler
- madler@alumni.caltech.edu
- */
-
-/* Substantially modified by Paul Jones for usage in bees */
-
 #include "crucible/crc64.h"
 
 #define POLY64REV 0xd800000000000000ULL
@@ -33,16 +5,13 @@
 namespace crucible {
 
 	static bool init = false;
-	static uint64_t CRCTable[8][256];
+	static uint64_t CRCTable[256];
 
 	static void init_crc64_table()
 	{
 		if (!init) {
-			uint64_t crc;
-
-			// Generate CRCs for all single byte sequences
-			for (int n = 0; n < 256; n++) {
-				uint64_t part = n;
+			for (int i = 0; i <= 255; i++) {
+				uint64_t part = i;
 				for (int j = 0; j < 8; j++) {
 					if (part & 1) {
 						part = (part >> 1) ^ POLY64REV;
@@ -50,53 +19,37 @@ namespace crucible {
 						part >>= 1;
 					}
 				}
-				CRCTable[0][n] = part;
-			}
-
-			// Generate nested CRC table for slice-by-8 lookup
-			for (int n = 0; n < 256; n++) {
-				crc = CRCTable[0][n];
-				for (int k = 1; k < 8; k++) {
-					crc = CRCTable[0][crc & 0xff] ^ (crc >> 8);
-					CRCTable[k][n] = crc;
-				}
+				CRCTable[i] = part;
 			}
 			init = true;
 		}
 	}
 
+	uint64_t
+	Digest::CRC::crc64(const char *s)
+	{
+		init_crc64_table();
+
+		uint64_t crc = 0;
+		for (; *s; s++) {
+			uint64_t temp1 = crc >> 8;
+			uint64_t temp2 = CRCTable[(crc ^ static_cast<uint64_t>(*s)) & 0xff];
+			crc = temp1 ^ temp2;
+		}
+
+		return crc;
+	}
+
 	uint64_t
 	Digest::CRC::crc64(const void *p, size_t len)
 	{
 		init_crc64_table();
-		const unsigned char *next = static_cast<const unsigned char *>(p);
+
 		uint64_t crc = 0;
-
-		// Process individual bytes until we reach an 8-byte aligned pointer
-		while (len && (reinterpret_cast<uintptr_t>(next) & 7) != 0) {
-			crc = CRCTable[0][(crc ^ *next++) & 0xff] ^ (crc >> 8);
-			len--;
-		}
-
-		// Fast middle processing, 8 bytes (aligned!) per loop
-		while (len >= 8) {
-			crc ^= *(reinterpret_cast< const uint64_t *>(next));
-			crc = CRCTable[7][crc & 0xff] ^
-				  CRCTable[6][(crc >> 8) & 0xff] ^
-				  CRCTable[5][(crc >> 16) & 0xff] ^
-				  CRCTable[4][(crc >> 24) & 0xff] ^
-				  CRCTable[3][(crc >> 32) & 0xff] ^
-				  CRCTable[2][(crc >> 40) & 0xff] ^
-				  CRCTable[1][(crc >> 48) & 0xff] ^
-				  CRCTable[0][crc >> 56];
-			next += 8;
-			len -= 8;
-		}
-
-		// Process remaining bytes (can't be larger than 8)
-		while (len) {
-			crc = CRCTable[0][(crc ^ *next++) & 0xff] ^ (crc >> 8);
-			len--;
+		for (const unsigned char *s = static_cast<const unsigned char *>(p); len; --len) {
+			uint64_t temp1 = crc >> 8;
+			uint64_t temp2 = CRCTable[(crc ^ *s++) & 0xff];
+			crc = temp1 ^ temp2;
 		}
 
 		return crc;

lib/execpipe.cc

@@ -0,0 +1,104 @@
+#include "crucible/execpipe.h"
+
+#include "crucible/chatter.h"
+#include "crucible/error.h"
+#include "crucible/process.h"
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+namespace crucible {
+	using namespace std;
+
+	void
+	redirect_stdin(const Fd &child_fd)
+	{
+		dup2_or_die(child_fd, STDIN_FILENO);
+	}
+
+	void
+	redirect_stdin_stdout(const Fd &child_fd)
+	{
+		dup2_or_die(child_fd, STDOUT_FILENO);
+		dup2_or_die(child_fd, STDIN_FILENO);
+	}
+
+	void
+	redirect_stdin_stdout_stderr(const Fd &child_fd)
+	{
+		dup2_or_die(child_fd, STDERR_FILENO);
+		dup2_or_die(child_fd, STDOUT_FILENO);
+		dup2_or_die(child_fd, STDIN_FILENO);
+	}
+
+	void
+	redirect_stdout_stderr(const Fd &child_fd)
+	{
+		dup2_or_die(child_fd, STDERR_FILENO);
+		dup2_or_die(child_fd, STDOUT_FILENO);
+	}
+
+	void
+	redirect_stdout(const Fd &child_fd)
+	{
+		dup2_or_die(child_fd, STDOUT_FILENO);
+	}
+
+	void
+	redirect_stderr(const Fd &child_fd)
+	{
+		dup2_or_die(child_fd, STDERR_FILENO);
+	}
+
+	Fd popen(function<int()> f, function<void(const Fd &child_fd)> import_fd_fn)
+	{
+		Fd parent_fd, child_fd;
+		{
+			pair<Fd, Fd> fd_pair = socketpair_or_die();
+			parent_fd = fd_pair.first;
+			child_fd = fd_pair.second;
+		}
+
+		pid_t fv;
+		DIE_IF_MINUS_ONE(fv = fork());
+
+		if (fv) {
+			child_fd->close();
+			return parent_fd;
+		} else {
+			int rv = EXIT_FAILURE;
+			catch_all([&]() {
+				parent_fd->close();
+				import_fd_fn(child_fd);
+				// system("ls -l /proc/$$/fd/ >&2");
+
+				rv = f();
+			});
+			_exit(rv);
+			cerr << "PID " << getpid() << " TID " << gettid() << "STILL ALIVE" << endl;
+			system("ls -l /proc/$$/task/ >&2");
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	string
+	read_all(Fd fd, size_t max_bytes, size_t chunk_bytes)
+	{
+		char buf[chunk_bytes];
+		string str;
+		size_t rv;
+		while (1) {
+			read_partial_or_die(fd, static_cast<void *>(buf), chunk_bytes, rv);
+			if (rv == 0) {
+				break;
+			}
+			if (max_bytes - str.size() < rv) {
+				THROW_ERROR(out_of_range, "Output size limit " << max_bytes << " exceeded by appending " << rv << " bytes read to " << str.size() << " already in string");
+			}
+			str.append(buf, rv);
+		}
+		return str;
+	}
+}

lib/extentwalker.cc

@@ -79,6 +79,17 @@ namespace crucible {
 			<< "] }";
 	}
 
+	Extent::Extent() :
+		m_begin(0),
+		m_end(0),
+		m_physical(0),
+		m_flags(0),
+		m_physical_len(0),
+		m_logical_len(0),
+		m_offset(0)
+	{
+	}
+
 	Extent::operator bool() const
 	{
 		THROW_CHECK2(invalid_argument, m_begin, m_end, m_end >= m_begin);
@@ -98,18 +109,6 @@ namespace crucible {
 		return m_begin == that.m_begin && m_end == that.m_end && m_physical == that.m_physical && m_flags == that.m_flags;
 	}
 
-	bool
-	Extent::compressed() const
-	{
-		return m_flags & FIEMAP_EXTENT_ENCODED;
-	}
-
-	uint64_t
-	Extent::bytenr() const
-	{
-		return compressed() ? m_physical : m_physical - m_offset;
-	}
-
 	ExtentWalker::ExtentWalker(Fd fd) :
 		m_fd(fd),
 		m_current(m_extents.begin())
@@ -469,7 +468,7 @@ namespace crucible {
 	BtrfsExtentWalker::Vec
 	BtrfsExtentWalker::get_extent_map(off_t pos)
 	{
-		BtrfsIoctlSearchKey sk(sc_extent_fetch_max * (sizeof(btrfs_file_extent_item) + sizeof(btrfs_ioctl_search_header)));
+		BtrfsIoctlSearchKey sk;
 		if (!m_root_fd) {
 			m_root_fd = m_fd;
 		}
@@ -520,26 +519,25 @@ namespace crucible {
 
 			auto type = call_btrfs_get(btrfs_stack_file_extent_type, i.m_data);
 			off_t len = -1;
-			switch (type) {
-				default:
+                        switch (type) {
+                                default:
 					cerr << "Unhandled file extent type " << type << " in root " << m_tree_id << " ino " << m_stat.st_ino << endl;
 					break;
-				case BTRFS_FILE_EXTENT_INLINE:
+                                case BTRFS_FILE_EXTENT_INLINE:
 					len = ranged_cast<off_t>(call_btrfs_get(btrfs_stack_file_extent_ram_bytes, i.m_data));
 					e.m_flags |= FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_NOT_ALIGNED;
 					// Inline extents are never obscured, so don't bother filling in m_physical_len, etc.
-					break;
-				case BTRFS_FILE_EXTENT_PREALLOC:
+                                        break;
+                                case BTRFS_FILE_EXTENT_PREALLOC:
 					e.m_flags |= Extent::PREALLOC;
-					// fallthrough
-				case BTRFS_FILE_EXTENT_REG: {
+                                case BTRFS_FILE_EXTENT_REG: {
 					e.m_physical = call_btrfs_get(btrfs_stack_file_extent_disk_bytenr, i.m_data);
 
 					// This is the length of the full extent (decompressed)
-					off_t ram = ranged_cast<off_t>(call_btrfs_get(btrfs_stack_file_extent_ram_bytes, i.m_data));
+                                        off_t ram = ranged_cast<off_t>(call_btrfs_get(btrfs_stack_file_extent_ram_bytes, i.m_data));
 
 					// This is the length of the part of the extent appearing in the file (decompressed)
-					len = ranged_cast<off_t>(call_btrfs_get(btrfs_stack_file_extent_num_bytes, i.m_data));
+                                        len = ranged_cast<off_t>(call_btrfs_get(btrfs_stack_file_extent_num_bytes, i.m_data));
 
 					// This is the offset from start of on-disk extent to the part we see in the file (decompressed)
 					// May be negative due to the kind of bug we're stuck with forever, so no cast range check

lib/fd.cc

@@ -230,14 +230,6 @@ namespace crucible {
 		}
 	}
 
-	void
-	ftruncate_or_die(int fd, off_t size)
-	{
-		if (::ftruncate(fd, size)) {
-			THROW_ERRNO("ftruncate: " << name_fd(fd) << " size " << size);
-		}
-	}
-
 	string
 	socket_domain_ntoa(int domain)
 	{
@@ -434,27 +426,6 @@ namespace crucible {
 		return pread_or_die(fd, text.data(), text.size(), offset);
 	}
 
-	template<>
-	void
-	pwrite_or_die<vector<uint8_t>>(int fd, const vector<uint8_t> &text, off_t offset)
-	{
-		return pwrite_or_die(fd, text.data(), text.size(), offset);
-	}
-
-	template<>
-	void
-	pwrite_or_die<vector<char>>(int fd, const vector<char> &text, off_t offset)
-	{
-		return pwrite_or_die(fd, text.data(), text.size(), offset);
-	}
-
-	template<>
-	void
-	pwrite_or_die<string>(int fd, const string &text, off_t offset)
-	{
-		return pwrite_or_die(fd, text.data(), text.size(), offset);
-	}
-
 	Stat::Stat()
 	{
 		memset_zero<stat>(this);
@@ -488,20 +459,6 @@ namespace crucible {
 		lstat(filename);
 	}
 
-	int
-	ioctl_iflags_get(int fd)
-	{
-		int attr = 0;
-		DIE_IF_MINUS_ONE(ioctl(fd, FS_IOC_GETFLAGS, &attr));
-		return attr;
-	}
-
-	void
-	ioctl_iflags_set(int fd, int attr)
-	{
-		DIE_IF_MINUS_ONE(ioctl(fd, FS_IOC_SETFLAGS, &attr));
-	}
-
 	string
 	readlink_or_die(const string &path)
 	{
@@ -527,22 +484,6 @@ namespace crucible {
 		THROW_ERROR(runtime_error, "readlink: maximum buffer size exceeded");
 	}
 
-	string
-	relative_path()
-	{
-		return __relative_path;
-	}
-
-	void
-	set_relative_path(string path)
-	{
-		path = path + "/";
-		for (string::size_type i = path.find("//"); i != string::npos; i = path.find("//")) {
-			path.erase(i, 1);
-		}
-		__relative_path = path;
-	}
-
 	// Turn a FD into a human-recognizable filename OR an error message.
 	string
 	name_fd(int fd)
@@ -550,12 +491,7 @@ namespace crucible {
 		try {
 			ostringstream oss;
 			oss << "/proc/self/fd/" << fd;
-			string path = readlink_or_die(oss.str());
-			if (!__relative_path.empty() && 0 == path.find(__relative_path))
-			{
-				path.erase(0, __relative_path.length());
-			}
-			return path;
+			return readlink_or_die(oss.str());
 		} catch (exception &e) {
 			return string(e.what());
 		}

lib/fs.cc

@@ -468,7 +468,6 @@ namespace crucible {
 		static const bits_ntoa_table table[] = {
 			NTOA_TABLE_ENTRY_ENUM(BTRFS_COMPRESS_ZLIB),
 			NTOA_TABLE_ENTRY_ENUM(BTRFS_COMPRESS_LZO),
-			NTOA_TABLE_ENTRY_ENUM(BTRFS_COMPRESS_ZSTD),
 			NTOA_TABLE_ENTRY_END()
 		};
 		return bits_ntoa(compress_type, table);
@@ -626,7 +625,7 @@ namespace crucible {
 	void
 	Fiemap::do_ioctl(int fd)
 	{
-		THROW_CHECK1(out_of_range, m_min_count, m_min_count <= m_max_count);
+		CHECK_CONSTRAINT(m_min_count, m_min_count <= m_max_count);
 
 		auto extent_count = m_min_count;
 		vector<char> ioctl_arg = vector_copy_struct<fiemap>(this);
@@ -708,29 +707,11 @@ namespace crucible {
 		return offset + len;
 	}
 
-	bool
-	BtrfsIoctlSearchHeader::operator<(const BtrfsIoctlSearchHeader &that) const
-	{
-		return tie(objectid, type, offset, len, transid) < tie(that.objectid, that.type, that.offset, that.len, that.transid);
-	}
-
 	bool
 	BtrfsIoctlSearchKey::do_ioctl_nothrow(int fd)
 	{
-		// Normally we like to be paranoid and fill empty bytes with zero,
-		// but these buffers can be huge.  80% of a 4GHz CPU huge.
-
-		// Keep the ioctl buffer from one run to the next to save on malloc costs
-		size_t target_buf_size = sizeof(btrfs_ioctl_search_args_v2) + m_buf_size;
-
-		thread_local vector<char> ioctl_arg;
-		if (ioctl_arg.size() < m_buf_size) {
-			ioctl_arg = vector_copy_struct<btrfs_ioctl_search_key>(this);
-			ioctl_arg.resize(target_buf_size);
-		} else {
-			memcpy(ioctl_arg.data(), static_cast<btrfs_ioctl_search_key*>(this), sizeof(btrfs_ioctl_search_key));
-		}
-
+		vector<char> ioctl_arg = vector_copy_struct<btrfs_ioctl_search_key>(this);
+		ioctl_arg.resize(sizeof(btrfs_ioctl_search_args_v2) + m_buf_size, 0);
 		btrfs_ioctl_search_args_v2 *ioctl_ptr = reinterpret_cast<btrfs_ioctl_search_args_v2 *>(ioctl_arg.data());
 
 		ioctl_ptr->buf_size = m_buf_size;
@@ -744,12 +725,13 @@ namespace crucible {
 		static_cast<btrfs_ioctl_search_key&>(*this) = ioctl_ptr->key;
 
 		m_result.clear();
+		m_result.reserve(nr_items);
 
 		size_t offset = pointer_distance(ioctl_ptr->buf, ioctl_ptr);
 		for (decltype(nr_items) i = 0; i < nr_items; ++i) {
 			BtrfsIoctlSearchHeader item;
 			offset = item.set_data(ioctl_arg, offset);
-			m_result.insert(item);
+			m_result.push_back(item);
 		}
 
 		return true;
@@ -852,7 +834,7 @@ namespace crucible {
 	}
 
 	string
-	btrfs_search_objectid_ntoa(uint64_t objectid)
+	btrfs_search_objectid_ntoa(unsigned objectid)
 	{
 		static const bits_ntoa_table table[] = {
 			NTOA_TABLE_ENTRY_ENUM(BTRFS_ROOT_TREE_OBJECTID),
@@ -924,7 +906,7 @@ namespace crucible {
 	ostream &
 	operator<<(ostream &os, const BtrfsIoctlSearchHeader &hdr)
 	{
-		os << "BtrfsIoctlSearchHeader { "
+		os << "BtrfsIoctlSearchHeader { " 
 			<< static_cast<const btrfs_ioctl_search_header &>(hdr)
 			<< ", data = ";
 		hexdump(os, hdr.m_data);
@@ -934,7 +916,7 @@ namespace crucible {
 	ostream &
 	operator<<(ostream &os, const BtrfsIoctlSearchKey &key)
 	{
-		os << "BtrfsIoctlSearchKey { "
+		os << "BtrfsIoctlSearchKey { " 
 			<< static_cast<const btrfs_ioctl_search_key &>(key)
 			<< ", buf_size = " << key.m_buf_size
 			<< ", buf[" << key.m_result.size() << "] = {";

lib/interp.cc

@@ -0,0 +1,96 @@
+#include "crucible/interp.h"
+
+#include "crucible/chatter.h"
+
+namespace crucible {
+	using namespace std;
+
+	int
+	Proc::exec(const ArgList &args)
+	{
+		return m_cmd(args);
+	}
+
+	Proc::Proc(const function<int(const ArgList &)> &f) :
+		m_cmd(f)
+	{
+	}
+
+	Command::~Command()
+	{
+	}
+
+	ArgList::ArgList(const char **argv)
+	{
+		while (argv && *argv) {
+			push_back(*argv++);
+		}
+	}
+
+	ArgList::ArgList(const vector<string> &&that) :
+		vector<string>(that)
+	{
+	}
+
+	Interp::~Interp()
+	{
+	}
+
+	Interp::Interp(const map<string, shared_ptr<Command> > &cmdlist) :
+		m_commands(cmdlist)
+	{
+	}
+
+	void
+	Interp::add_command(const string &name, const shared_ptr<Command> &command)
+	{
+		m_commands[name] = command;
+	}
+
+	int
+	Interp::exec(const ArgList &args)
+	{
+		auto next_arg = args.begin();
+		++next_arg;
+		return m_commands.at(args[0])->exec(vector<string>(next_arg, args.end()));
+	}
+
+	ArgParser::~ArgParser()
+	{
+	}
+
+	ArgParser::ArgParser()
+	{
+	}
+
+	void
+	ArgParser::add_opt(string opt, ArgActor actor)
+	{
+		m_string_opts[opt] = actor;
+	}
+
+	void
+	ArgParser::parse_backend(void *t, const ArgList &args)
+	{
+		bool quote_args = false;
+		for (string arg : args) {
+			if (quote_args) {
+				cerr << "arg: '" << arg << "'" << endl;
+				continue;
+			}
+			if (arg == "--") {
+				quote_args = true;
+				continue;
+			}
+			if (arg.compare(0, 2, "--") == 0) {
+				auto found = m_string_opts.find(arg.substr(2, string::npos));
+				if (found != m_string_opts.end()) {
+					found->second.predicate(t, "foo");
+				}
+				(void)t;
+			}
+		}
+	}
+
+
+};

lib/ntoa.cc

@@ -7,7 +7,7 @@
 namespace crucible {
 	using namespace std;
 
-	string bits_ntoa(unsigned long long n, const bits_ntoa_table *table)
+	string bits_ntoa(unsigned long n, const bits_ntoa_table *table)
 	{
 		string out;
 		while (n && table->a) {

makeflags

@@ -1,4 +1,4 @@
-CCFLAGS  = -Wall -Wextra -Werror -O3 -march=native -I../include -ggdb -D_FILE_OFFSET_BITS=64
-# CCFLAGS  = -Wall -Wextra -Werror -O0 -I../include -ggdb -fpic -D_FILE_OFFSET_BITS=64
+CCFLAGS  = -Wall -Wextra -Werror -O3 -I../include -ggdb -fpic
+# CCFLAGS  = -Wall -Wextra -Werror -O0 -I../include -ggdb -fpic
 CFLAGS   = $(CCFLAGS) -std=c99
 CXXFLAGS = $(CCFLAGS) -std=c++11 -Wold-style-cast

scripts/beesd.conf.sample

@@ -1,34 +0,0 @@
-## Config for Bees: /etc/bees/beesd.conf.sample
-## https://github.com/Zygo/bees
-## It's a default values, change it, if needed
-
-# How to use?
-# Copy this file to a new file name and adjust the UUID below
-
-# Which FS will be used
-UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
-
-## System Vars
-# Change carefully
-# WORK_DIR=/run/bees/
-# MNT_DIR="$WORK_DIR/mnt/$UUID"
-# BEESHOME="$MNT_DIR/.beeshome"
-# BEESSTATUS="$WORK_DIR/$UUID.status"
-
-## Default options to apply, see --help for details
-# OPTIONS="--relative-paths --notimestamps"
-
-## Bees DB size
-# Hash Table Sizing
-# sHash table entries are 16 bytes each
-# (64-bit hash, 52-bit block number, and some metadata bits)
-# Each entry represents a minimum of 4K on disk.
-# unique data size    hash table size    average dedup block size
-#     1TB                 4GB                  4K
-#     1TB                 1GB                 16K
-#     1TB               256MB                 64K
-#     1TB                16MB               1024K
-#    64TB                 1GB               1024K
-#
-# Size MUST be power of 16M
-# DB_SIZE=$((64*$AL16M)) # 1G in bytes

scripts/beesd.in

@@ -1,119 +0,0 @@
-#!/bin/bash
-
-## Helpful functions
-INFO(){ echo "INFO:" "$@"; }
-ERRO(){ echo "ERROR:" "$@"; exit 1; }
-YN(){ [[ "$1" =~ (1|Y|y) ]]; }
-
-## Global vars
-export BEESHOME BEESSTATUS
-export WORK_DIR CONFIG_DIR
-export CONFIG_FILE
-export UUID AL16M
-
-readonly AL16M="$((16*1024*1024))"
-readonly CONFIG_DIR=@PREFIX@/etc/bees/
-
-## Pre checks
-{
-    [ ! -d "$CONFIG_DIR" ] && ERRO "Missing: $CONFIG_DIR"
-    [ "$UID" == "0" ] || ERRO "Must be run as root"
-}
-
-command -v @LIBEXEC_PREFIX@/bees &> /dev/null || ERRO "Missing 'bees' agent"
-
-## Parse args
-ARGUMENTS=()
-while [ $# -gt 0 ]; do
-    case "$1" in
-        -*)
-            ARGUMENTS+=($1)
-        ;;
-        *)
-            if [ -z "$UUID" ]; then
-                UUID="$1"
-            else
-                ERRO "Only one filesystem may be supplied"
-            fi
-        ;;
-    esac
-    shift
-done
-
-case "$UUID" in
-    *-*-*-*-*)
-        FILE_CONFIG=""
-        for file in "$CONFIG_DIR"/*.conf; do
-            [ ! -f "$file" ] && continue
-            if grep -q "$UUID" "$file"; then
-                INFO "Find $UUID in $file, use as conf"
-                FILE_CONFIG="$file"
-            fi
-        done
-        [ ! -f "$FILE_CONFIG" ] && ERRO "No config for $UUID"
-        source "$FILE_CONFIG"
-    ;;
-    *)
-        echo "beesd [options] <btrfs_uuid>"
-        exit 1
-    ;;
-esac
-
-WORK_DIR="${WORK_DIR:-/run/bees/}"
-MNT_DIR="${MNT_DIR:-$WORK_DIR/mnt/$UUID}"
-BEESHOME="${BEESHOME:-$MNT_DIR/.beeshome}"
-BEESSTATUS="${BEESSTATUS:-$WORK_DIR/$UUID.status}"
-DB_SIZE="${DB_SIZE:-$((64*AL16M))}"
-
-INFO "Check: Disk exists"
-if [ ! -b "/dev/disk/by-uuid/$UUID" ]; then
-    ERRO "Missing disk: /dev/disk/by-uuid/$UUID"
-fi
-
-is_btrfs(){ [ "$(blkid -s TYPE -o value "$1")" == "btrfs" ]; }
-
-INFO "Check: Disk with btrfs"
-if ! is_btrfs "/dev/disk/by-uuid/$UUID"; then
-    ERRO "Disk not contain btrfs: /dev/disk/by-uuid/$UUID"
-fi
-
-INFO "WORK DIR: $WORK_DIR"
-mkdir -p "$WORK_DIR" || exit 1
-
-INFO "MOUNT DIR: $MNT_DIR"
-mkdir -p "$MNT_DIR" || exit 1
-
-umount_w(){ mountpoint -q "$1" && umount -l "$1"; }
-force_umount(){ umount_w "$MNT_DIR"; }
-trap force_umount SIGINT SIGTERM EXIT
-
-mount -osubvolid=5 /dev/disk/by-uuid/$UUID "$MNT_DIR" || exit 1
-
-if [ ! -d "$BEESHOME" ]; then
-    INFO "Create subvol $BEESHOME for store bees data"
-    btrfs sub cre "$BEESHOME"
-else
-    btrfs sub show "$BEESHOME" &> /dev/null || ERRO "$BEESHOME MUST BE A SUBVOL!"
-fi
-
-# Check DB size
-{
-    DB_PATH="$BEESHOME/beeshash.dat"
-    touch "$DB_PATH"
-    OLD_SIZE="$(du -b "$DB_PATH" | sed 's/\t/ /g' | cut -d' ' -f1)"
-    NEW_SIZE="$DB_SIZE"
-    if (( "$NEW_SIZE"%AL16M > 0 )); then
-        ERRO "DB_SIZE Must be multiple of 16M"
-    fi
-    if (( "$OLD_SIZE" != "$NEW_SIZE" )); then
-        INFO "Resize db: $OLD_SIZE -> $NEW_SIZE"
-        [ -f "$BEESHOME/beescrawl.$UUID.dat" ] && rm "$BEESHOME/beescrawl.$UUID.dat"
-        truncate -s $NEW_SIZE $DB_PATH
-    fi
-    chmod 700 "$DB_PATH"
-}
-
-MNT_DIR="${MNT_DIR//\/\//\/}"
-
-cd "$MNT_DIR"
-@LIBEXEC_PREFIX@/bees "${ARGUMENTS[@]}" $OPTIONS "$MNT_DIR"

scripts/beesd@.service.in

@@ -1,25 +0,0 @@
-[Unit]
-Description=Bees (%i)
-Documentation=https://github.com/Zygo/bees
-After=sysinit.target
-
-[Service]
-Type=simple
-ExecStart=/usr/sbin/beesd %i
-Nice=19
-KillMode=control-group
-KillSignal=SIGTERM
-CPUShares=128
-StartupCPUShares=256
-BlockIOWeight=100
-StartupBlockIOWeight=250
-IOSchedulingClass=idle
-IOSchedulingPriority=7
-CPUSchedulingPolicy=batch
-Nice=19
-Restart=on-abnormal
-CPUAccounting=true
-MemoryAccounting=true
-
-[Install]
-WantedBy=basic.target

src/.gitignore

@@ -1 +0,0 @@
-bees-version.[ch]

src/Makefile

@@ -1,5 +1,6 @@
 PROGRAMS = \
 	../bin/bees \
+	../bin/fanotify-watch \
 	../bin/fiemap \
 	../bin/fiewalk \
 
@@ -8,16 +9,12 @@ all: $(PROGRAMS) depends.mk
 include ../makeflags
 
 LIBS = -lcrucible -lpthread
-LDFLAGS = -L../lib
+LDFLAGS = -L../lib -Wl,-rpath=$(shell realpath ../lib)
 
 depends.mk: Makefile *.cc
 	for x in *.cc; do $(CXX) $(CXXFLAGS) -M "$$x"; done > depends.mk.new
 	mv -fv depends.mk.new depends.mk
 
-bees-version.c: Makefile *.cc *.h
-	echo "const char *BEES_VERSION = \"$(shell git describe --always --dirty || echo UNKNOWN)\";" > bees-version.new.c
-	mv -f bees-version.new.c bees-version.c
-
 -include depends.mk
 
 %.o: %.cc %.h
@@ -35,11 +32,9 @@ BEES_OBJS = \
 	bees-roots.o \
 	bees-thread.o \
 	bees-types.o \
-	bees-version.o \
 
 ../bin/bees: $(BEES_OBJS)
 	$(CXX) $(CXXFLAGS) -o "$@" $(BEES_OBJS) $(LDFLAGS) $(LIBS)
 
 clean:
-	-rm -fv bees-version.h
-	-rm -fv *.o bees-version.c
+	-rm -fv *.o

src/bees-context.cc

@@ -1,12 +1,10 @@
 #include "bees.h"
 
 #include "crucible/limits.h"
-#include "crucible/process.h"
 #include "crucible/string.h"
 
 #include <fstream>
 #include <iostream>
-#include <vector>
 
 using namespace crucible;
 using namespace std;
@@ -25,19 +23,11 @@ getenv_or_die(const char *name)
 BeesFdCache::BeesFdCache()
 {
 	m_root_cache.func([&](shared_ptr<BeesContext> ctx, uint64_t root) -> Fd {
-		Timer open_timer;
-		auto rv = ctx->roots()->open_root_nocache(root);
-		BEESCOUNTADD(open_root_ms, open_timer.age() * 1000);
-		return rv;
+		return ctx->roots()->open_root_nocache(root);
 	});
-	m_root_cache.max_size(BEES_ROOT_FD_CACHE_SIZE);
 	m_file_cache.func([&](shared_ptr<BeesContext> ctx, uint64_t root, uint64_t ino) -> Fd {
-		Timer open_timer;
-		auto rv = ctx->roots()->open_root_ino_nocache(root, ino);
-		BEESCOUNTADD(open_ino_ms, open_timer.age() * 1000);
-		return rv;
+		return ctx->roots()->open_root_ino_nocache(root, ino);
 	});
-	m_file_cache.max_size(BEES_FILE_FD_CACHE_SIZE);
 }
 
 Fd
@@ -58,12 +48,6 @@ BeesFdCache::open_root(shared_ptr<BeesContext> ctx, uint64_t root)
 Fd
 BeesFdCache::open_root_ino(shared_ptr<BeesContext> ctx, uint64_t root, uint64_t ino)
 {
-	if (m_file_cache_timer.age() > BEES_COMMIT_INTERVAL) {
-		BEESINFO("Clearing open FD cache to enable file delete");
-		m_file_cache.clear();
-		m_file_cache_timer.reset();
-		BEESCOUNT(open_clear);
-	}
 	return m_file_cache(ctx, root, ino);
 }
 
@@ -74,6 +58,97 @@ BeesFdCache::insert_root_ino(shared_ptr<BeesContext> ctx, Fd fd)
 	return m_file_cache.insert(fd, ctx, fid.root(), fid.ino());
 }
 
+mutex BeesWorkQueueBase::s_mutex;
+set<BeesWorkQueueBase*> BeesWorkQueueBase::s_all_workers;
+
+BeesWorkQueueBase::BeesWorkQueueBase(const string &name) :
+	m_name(name)
+{
+}
+
+BeesWorkQueueBase::~BeesWorkQueueBase()
+{
+	unique_lock<mutex> lock(s_mutex);
+	s_all_workers.erase(this);
+}
+
+void
+BeesWorkQueueBase::for_each_work_queue(std::function<void (BeesWorkQueueBase*)> f)
+{
+	unique_lock<mutex> lock(s_mutex);
+	for (auto i : s_all_workers) {
+		f(i);
+	}
+}
+
+string
+BeesWorkQueueBase::name() const
+{
+	return m_name;
+}
+
+void
+BeesWorkQueueBase::name(const string &new_name)
+{
+	m_name = new_name;
+}
+
+template <class Task>
+BeesWorkQueue<Task>::~BeesWorkQueue()
+{
+}
+
+template <class Task>
+BeesWorkQueue<Task>::BeesWorkQueue(const string &name) :
+	BeesWorkQueueBase(name)
+{
+	unique_lock<mutex> lock(s_mutex);
+	s_all_workers.insert(this);
+}
+
+template <class Task>
+void
+BeesWorkQueue<Task>::push_active(const Task &t)
+{
+	BEESNOTE("pushing task " << t);
+	m_active_queue.push(t);
+}
+
+template <class Task>
+void
+BeesWorkQueue<Task>::push_active(const Task &t, size_t limit)
+{
+	// BEESNOTE("pushing limit " << limit << " task " << t);
+	m_active_queue.push_wait(t, limit);
+}
+
+template <class Task>
+size_t
+BeesWorkQueue<Task>::active_size() const
+{
+	return m_active_queue.size();
+}
+
+template <class Task>
+list<string>
+BeesWorkQueue<Task>::peek_active(size_t count) const
+{
+	list<string> rv;
+	for (auto i : m_active_queue.peek(count)) {
+		ostringstream oss;
+		oss << i;
+		rv.push_back(oss.str());
+	}
+	return rv;
+}
+
+template <class Task>
+Task
+BeesWorkQueue<Task>::pop()
+{
+	return m_active_queue.pop();
+}
+
 void
 BeesContext::dump_status()
 {
@@ -100,6 +175,12 @@ BeesContext::dump_status()
 			ofs << "\ttid " << t.first << ": " << t.second << "\n";
 		}
 
+		BeesWorkQueueBase::for_each_work_queue([&](BeesWorkQueueBase *worker) {
+			ofs << "QUEUE: " << worker->name() << " active: " << worker->active_size() << "\n";
+			for (auto t : worker->peek_active(10)) {
+				ofs << "\t" << t << "\n";
+			}
+		});
 		ofs.close();
 
 		BEESNOTE("renaming status file '" << status_file << "'");
@@ -135,6 +216,10 @@ BeesContext::show_progress()
 		};
 		lastProgressStats = thisStats;
 
+		BeesWorkQueueBase::for_each_work_queue([&](BeesWorkQueueBase *worker) {
+			BEESLOG("QUEUE: " << worker->name() << " active: " << worker->active_size());
+		});
+
 		BEESLOG("THREADS:");
 
 		for (auto t : BeesNote::get_status()) {	
@@ -143,25 +228,15 @@ BeesContext::show_progress()
 	}
 }
 
-Fd
-BeesContext::home_fd()
-{
-	const char *base_dir = getenv("BEESHOME");
-	if (!base_dir) {
-		base_dir = ".beeshome";
-	}
-	m_home_fd = openat(root_fd(), base_dir, FLAGS_OPEN_DIR);
-	if (!m_home_fd) {
-		THROW_ERRNO("openat: " << name_fd(root_fd()) << " / " << base_dir);
-	}
-	return m_home_fd;
-}
-
 BeesContext::BeesContext(shared_ptr<BeesContext> parent) :
 	m_parent_ctx(parent)
 {
-	// m_extent_lock_set.max_size(bees_worker_thread_count());;
+	auto base_dir = getenv_or_die("BEESHOME");
+	BEESLOG("BEESHOME = " << base_dir);
+	m_home_fd = open_or_die(base_dir, FLAGS_OPEN_DIR);
 	if (m_parent_ctx) {
+		m_hash_table = m_parent_ctx->hash_table();
+		m_hash_table->set_shared(true);
 		m_fd_cache = m_parent_ctx->fd_cache();
 	}
 }
@@ -169,23 +244,44 @@ BeesContext::BeesContext(shared_ptr<BeesContext> parent) :
 bool
 BeesContext::dedup(const BeesRangePair &brp)
 {
-	// Open the files
+	// TOOLONG and NOTE can retroactively fill in the filename details, but LOG can't
+	BEESNOTE("dedup " << brp);
+
 	brp.first.fd(shared_from_this());
 	brp.second.fd(shared_from_this());
 
-	BEESNOTE("dedup " << brp);
+#if 0
+	// This avoids some sort of kernel race condition;
+	// however, it also doubles our dedup times.
+	// Is avoiding a crash every few weeks worth it?
+	bees_sync(brp.first.fd());
+#endif
+
 	BEESTOOLONG("dedup " << brp);
 
+	thread_local BeesFileId tl_first_fid, tl_second_fid;
+	if (tl_first_fid != brp.first.fid()) {
+		BEESLOG("dedup: src " << name_fd(brp.first.fd()));
+		tl_first_fid = brp.first.fid();
+		tl_second_fid = BeesFileId();
+	}
+	ostringstream dst_line;
+	dst_line << "       dst " << pretty(brp.first.size()) << " [" << to_hex(brp.first.begin()) << ".." << to_hex(brp.first.end()) << "]";
+	if (brp.first.begin() != brp.second.begin()) {
+		dst_line << " [" << to_hex(brp.second.begin()) << ".." << to_hex(brp.second.end()) << "]";
+	}
 	BeesAddress first_addr(brp.first.fd(), brp.first.begin());
 	BeesAddress second_addr(brp.second.fd(), brp.second.begin());
-
-	BEESLOG("dedup: src " << pretty(brp.first.size())  << " [" << to_hex(brp.first.begin())  << ".." << to_hex(brp.first.end())  << "] {" << first_addr  << "} " << name_fd(brp.first.fd()));
-	BEESLOG("       dst " << pretty(brp.second.size()) << " [" << to_hex(brp.second.begin()) << ".." << to_hex(brp.second.end()) << "] {" << second_addr << "} " << name_fd(brp.second.fd()));
-
+	dst_line << " (" << first_addr << "->" << second_addr << ")";
 	if (first_addr.get_physical_or_zero() == second_addr.get_physical_or_zero()) {
 		BEESLOGTRACE("equal physical addresses in dedup");
 		BEESCOUNT(bug_dedup_same_physical);
 	}
+	if (tl_second_fid != brp.second.fid()) {
+		dst_line << " " << name_fd(brp.second.fd());
+		tl_second_fid = brp.second.fid();
+	}
+	BEESLOG(dst_line.str());
 
 	THROW_CHECK1(invalid_argument, brp, !brp.first.overlaps(brp.second));
 	THROW_CHECK1(invalid_argument, brp, brp.first.size() == brp.second.size());
@@ -230,7 +326,6 @@ BeesContext::rewrite_file_range(const BeesFileRange &bfr)
 	// BEESLOG("\torig_bbd " << orig_bbd);
 	BeesBlockData dup_bbd(dup_brp.first.fd(), dup_brp.first.begin(), min(BLOCK_SIZE_SUMS, dup_brp.first.size()));
 	// BEESLOG("BeesResolver br(..., " << bfr << ")");
-	BEESTRACE("BeesContext::rewrite_file_range calling BeesResolver " << bfr);
 	BeesResolver br(m_ctx, BeesAddress(bfr.fd(), bfr.begin()));
 	// BEESLOG("\treplace_src " << dup_bbd);
 	br.replace_src(dup_bbd);
@@ -426,7 +521,6 @@ BeesContext::scan_one_extent(const BeesFileRange &bfr, const Extent &e)
 			if (found_addr.is_toxic()) {
 				BEESINFO("WORKAROUND: abandoned toxic match for hash " << hash << " addr " << found_addr);
 				// Don't push these back in because we'll never delete them.
-				// Extents may become non-toxic so give them a chance to expire.
 				// hash_table->push_front_hash_addr(hash, found_addr);
 				BEESCOUNT(scan_toxic_hash);
 				return bfr;
@@ -437,16 +531,17 @@ BeesContext::scan_one_extent(const BeesFileRange &bfr, const Extent &e)
 			catch_all([&]() {
 				BEESNOTE("resolving " << found_addr << " matched " << bbd);
 				BEESTRACE("resolving " << found_addr << " matched " << bbd);
-				BEESTRACE("BeesContext::scan_one_extent calling BeesResolver " << found_addr);
 				BeesResolver resolved(m_ctx, found_addr);
 				// Toxic extents are really toxic
 				if (resolved.is_toxic()) {
 					BEESINFO("WORKAROUND: abandoned toxic match at found_addr " << found_addr << " matching bbd " << bbd);
 					BEESCOUNT(scan_toxic_match);
-					// Make sure we never see this hash again.
-					// It has become toxic since it was inserted into the hash table.
+#if 0
+					// Don't push these back in because we'll never delete them.
+					// Make sure we never see this hash again
 					found_addr.set_toxic();
 					hash_table->push_front_hash_addr(hash, found_addr);
+#endif
 					abandon_extent = true;
 				} else if (!resolved.count()) {
 					BEESCOUNT(scan_resolve_zero);
@@ -668,7 +763,13 @@ BeesContext::scan_one_extent(const BeesFileRange &bfr, const Extent &e)
 
 	// Visualize
 	if (bar != string(block_count, '.')) {
-		BEESLOG("scan: " << pretty(e.size()) << " " << to_hex(e.begin()) << " [" << bar << "] " << to_hex(e.end()) << ' ' << name_fd(bfr.fd()));
+		thread_local BeesFileId last_fid;
+		string file_name;
+		if (bfr.fid() != last_fid) {
+			last_fid = bfr.fid();
+			file_name = " " + name_fd(bfr.fd());
+		}
+		BEESLOG("scan: " << pretty(e.size()) << " " << to_hex(e.begin()) << " [" << bar << "] " << to_hex(e.end()) << file_name);
 	}
 
 	return bfr;
@@ -720,9 +821,6 @@ BeesContext::scan_forward(const BeesFileRange &bfr)
 			e = ew.current();
 
 			catch_all([&]() {
-				uint64_t extent_bytenr = e.bytenr();
-				BEESNOTE("waiting for extent bytenr " << to_hex(extent_bytenr));
-				auto extent_lock = m_extent_lock_set.make_lock(extent_bytenr);
 				Timer one_extent_timer;
 				return_bfr = scan_one_extent(bfr, e);
 				BEESCOUNTADD(scanf_extent_ms, one_extent_timer.age() * 1000);
@@ -754,19 +852,12 @@ BeesContext::resolve_addr_uncached(BeesAddress addr)
 {
 	THROW_CHECK1(invalid_argument, addr, !addr.is_magic());
 	THROW_CHECK0(invalid_argument, !!root_fd());
-
-	// To avoid hammering all the cores with long-running ioctls,
-	// only do one resolve at any given time.
-	BEESNOTE("waiting to resolve addr " << addr);
-	auto lock = bees_ioctl_lock_set.make_lock(gettid());
-
 	Timer resolve_timer;
 
 	// There is no performance benefit if we restrict the buffer size.
         BtrfsIoctlLogicalInoArgs log_ino(addr.get_physical_or_zero());
 
 	{
-		BEESNOTE("resolving addr " << addr);
 		BEESTOOLONG("Resolving addr " << addr << " in " << root_path() << " refs " << log_ino.m_iors.size());
 		if (log_ino.do_ioctl_nothrow(root_fd())) {
 			BEESCOUNT(resolve_ok);
@@ -821,9 +912,8 @@ BeesContext::set_root_fd(Fd fd)
 	m_root_uuid = fsinfo.uuid();
 	BEESLOG("Filesystem UUID is " << m_root_uuid);
 
-	// 65536 is big enough for two max-sized extents.
-	// Need enough total space in the cache for the maximum number of active threads.
-	m_resolve_cache.max_size(65536 * bees_worker_thread_count());
+	// 65536 is big enough for two max-sized extents
+	m_resolve_cache.max_size(65536);
 	m_resolve_cache.func([&](BeesAddress addr) -> BeesResolveAddrResult {
 		return resolve_addr_uncached(addr);
 	});
@@ -863,8 +953,7 @@ BeesContext::tmpfile()
 	if (!m_tmpfiles[this_thread::get_id()]) {
 		m_tmpfiles[this_thread::get_id()] = make_shared<BeesTempFile>(shared_from_this());
 	}
-	auto rv = m_tmpfiles[this_thread::get_id()];
-	return rv;
+	return m_tmpfiles[this_thread::get_id()];
 }
 
 shared_ptr<BeesFdCache>
@@ -875,8 +964,7 @@ BeesContext::fd_cache()
 	if (!m_fd_cache) {
 		m_fd_cache = make_shared<BeesFdCache>();
 	}
-	auto rv = m_fd_cache;
-	return rv;
+	return m_fd_cache;
 }
 
 shared_ptr<BeesRoots>
@@ -887,8 +975,7 @@ BeesContext::roots()
 	if (!m_roots) {
 		m_roots = make_shared<BeesRoots>(shared_from_this());
 	}
-	auto rv = m_roots;
-	return rv;
+	return m_roots;
 }
 
 shared_ptr<BeesHashTable>
@@ -899,8 +986,7 @@ BeesContext::hash_table()
 	if (!m_hash_table) {
 		m_hash_table = make_shared<BeesHashTable>(shared_from_this(), "beeshash.dat");
 	}
-	auto rv = m_hash_table;
-	return rv;
+	return m_hash_table;
 }
 
 void
@@ -916,3 +1002,8 @@ BeesContext::insert_root_ino(Fd fd)
 {
 	fd_cache()->insert_root_ino(shared_from_this(), fd);
 }
+
+// instantiate templates for linkage ----------------------------------------
+
+template class BeesWorkQueue<BeesFileRange>;
+template class BeesWorkQueue<BeesRangePair>;

src/bees-hash.cc

@@ -11,6 +11,13 @@
 using namespace crucible;
 using namespace std;
 
+static inline
+bool
+using_any_madvise()
+{
+	return true;
+}
+
 ostream &
 operator<<(ostream &os, const BeesHash &bh)
 {
@@ -24,16 +31,14 @@ operator<<(ostream &os, const BeesHashTable::Cell &bhte)
 		  << BeesAddress(bhte.e_addr) << " }";
 }
 
-#if 0
-static
 void
-dump_bucket_locked(BeesHashTable::Cell *p, BeesHashTable::Cell *q)
+dump_bucket(BeesHashTable::Cell *p, BeesHashTable::Cell *q)
 {
+	// Must be called while holding m_bucket_mutex
 	for (auto i = p; i < q; ++i) {
 		BEESLOG("Entry " << i - p << " " << *i);
 	}
 }
-#endif
 
 const bool VERIFY_CLEARS_BUGS = false;
 
@@ -93,81 +98,68 @@ BeesHashTable::get_extent_range(HashType hash)
 	return make_pair(bp, ep);
 }
 
-bool
-BeesHashTable::flush_dirty_extent(uint64_t extent_index)
-{
-	BEESNOTE("flushing extent #" << extent_index << " of " << m_extents << " extents");
-
-	auto lock = lock_extent_by_index(extent_index);
-
-	// Not dirty, nothing to do
-	if (!m_extent_metadata.at(extent_index).m_dirty) {
-		return false;
-	}
-
-	bool wrote_extent = false;
-
-	catch_all([&]() {
-		uint8_t *dirty_extent     = m_extent_ptr[extent_index].p_byte;
-		uint8_t *dirty_extent_end = m_extent_ptr[extent_index + 1].p_byte;
-		THROW_CHECK1(out_of_range, dirty_extent,     dirty_extent     >= m_byte_ptr);
-		THROW_CHECK1(out_of_range, dirty_extent_end, dirty_extent_end <= m_byte_ptr_end);
-		THROW_CHECK2(out_of_range, dirty_extent_end, dirty_extent, dirty_extent_end - dirty_extent == BLOCK_SIZE_HASHTAB_EXTENT);
-		BEESTOOLONG("pwrite(fd " << m_fd << " '" << name_fd(m_fd)<< "', length " << to_hex(dirty_extent_end - dirty_extent) << ", offset " << to_hex(dirty_extent - m_byte_ptr) << ")");
-		// Copy the extent because we might be stuck writing for a while
-		vector<uint8_t> extent_copy(dirty_extent, dirty_extent_end);
-
-		// Mark extent non-dirty while we still hold the lock
-		m_extent_metadata.at(extent_index).m_dirty = false;
-
-		// Release the lock
-		lock.unlock();
-
-		// Write the extent (or not)
-		pwrite_or_die(m_fd, extent_copy, dirty_extent - m_byte_ptr);
-		BEESCOUNT(hash_extent_out);
-
-		wrote_extent = true;
-	});
-
-	BEESNOTE("flush rate limited after extent #" << extent_index << " of " << m_extents << " extents");
-	m_flush_rate_limit.sleep_for(BLOCK_SIZE_HASHTAB_EXTENT);
-	return wrote_extent;
-}
-
 void
 BeesHashTable::flush_dirty_extents()
 {
+	if (using_shared_map()) return;
+
 	THROW_CHECK1(runtime_error, m_buckets, m_buckets > 0);
 
-	uint64_t wrote_extents = 0;
-	for (size_t extent_index = 0; extent_index < m_extents; ++extent_index) {
-		if (flush_dirty_extent(extent_index)) {
-			++wrote_extents;
-		}
+	unique_lock<mutex> lock(m_extent_mutex);
+	auto dirty_extent_copy = m_buckets_dirty;
+	m_buckets_dirty.clear();
+	if (dirty_extent_copy.empty()) {
+		BEESNOTE("idle");
+		m_condvar.wait(lock);
+		return; // please call later, i.e. immediately
 	}
+	lock.unlock();
 
-	BEESNOTE("idle after writing " << wrote_extents << " of " << m_extents << " extents");
-	unique_lock<mutex> lock(m_dirty_mutex);
-	m_dirty_condvar.wait(lock);
+	size_t extent_counter = 0;
+	for (auto extent_number : dirty_extent_copy) {
+		++extent_counter;
+		BEESNOTE("flush extent #" << extent_number << " (" << extent_counter << " of " << dirty_extent_copy.size() << ")");
+		catch_all([&]() {
+			uint8_t *dirty_extent     = m_extent_ptr[extent_number].p_byte;
+			uint8_t *dirty_extent_end = m_extent_ptr[extent_number + 1].p_byte;
+			THROW_CHECK1(out_of_range, dirty_extent,     dirty_extent     >= m_byte_ptr);
+			THROW_CHECK1(out_of_range, dirty_extent_end, dirty_extent_end <= m_byte_ptr_end);
+			if (using_shared_map()) {
+				BEESTOOLONG("flush extent " << extent_number);
+				copy(dirty_extent, dirty_extent_end, dirty_extent);
+			} else {
+				BEESTOOLONG("pwrite(fd " << m_fd << " '" << name_fd(m_fd)<< "', length " << to_hex(dirty_extent_end - dirty_extent) << ", offset " << to_hex(dirty_extent - m_byte_ptr) << ")");
+				// Page locks slow us down more than copying the data does
+				vector<uint8_t> extent_copy(dirty_extent, dirty_extent_end);
+				pwrite_or_die(m_fd, extent_copy, dirty_extent - m_byte_ptr);
+				BEESCOUNT(hash_extent_out);
+			}
+		});
+		BEESNOTE("flush rate limited at extent #" << extent_number << " (" << extent_counter << " of " << dirty_extent_copy.size() << ")");
+		m_flush_rate_limit.sleep_for(BLOCK_SIZE_HASHTAB_EXTENT);
+	}
 }
 
 void
-BeesHashTable::set_extent_dirty_locked(uint64_t extent_index)
+BeesHashTable::set_extent_dirty(HashType hash)
 {
-	// Must already be locked
-	m_extent_metadata.at(extent_index).m_dirty = true;
-
-	// Signal writeback thread
-	unique_lock<mutex> dirty_lock(m_dirty_mutex);
-	m_dirty_condvar.notify_one();
+	if (using_shared_map()) return;
+	THROW_CHECK1(runtime_error, m_buckets, m_buckets > 0);
+	auto pr = get_extent_range(hash);
+	uint64_t extent_number = reinterpret_cast<Extent *>(pr.first) - m_extent_ptr;
+	THROW_CHECK1(runtime_error, extent_number, extent_number < m_extents);
+	unique_lock<mutex> lock(m_extent_mutex);
+	m_buckets_dirty.insert(extent_number);
+	m_condvar.notify_one();
 }
 
 void
 BeesHashTable::writeback_loop()
 {
-	while (true) {
-		flush_dirty_extents();
+	if (!using_shared_map()) {
+		while (1) {
+			flush_dirty_extents();
+		}
 	}
 }
 
@@ -203,13 +195,13 @@ BeesHashTable::prefetch_loop()
 		size_t unaligned_eof_count = 0;
 
 		for (uint64_t ext = 0; ext < m_extents; ++ext) {
-			BEESNOTE("prefetching hash table extent " << ext << " of " << m_extents);
+			BEESNOTE("prefetching hash table extent " << ext << " of " << m_extent_ptr_end - m_extent_ptr);
 			catch_all([&]() {
-				fetch_missing_extent_by_index(ext);
+				fetch_missing_extent(ext * c_buckets_per_extent);
 
-				BEESNOTE("analyzing hash table extent " << ext << " of " << m_extents);
+				BEESNOTE("analyzing hash table extent " << ext << " of " << m_extent_ptr_end - m_extent_ptr);
 				bool duplicate_bugs_found = false;
-				auto lock = lock_extent_by_index(ext);
+				unique_lock<mutex> lock(m_bucket_mutex);
 				for (Bucket *bucket = m_extent_ptr[ext].p_buckets; bucket < m_extent_ptr[ext + 1].p_buckets; ++bucket) {
 					if (verify_cell_range(bucket[0].p_cells, bucket[1].p_cells)) {
 						duplicate_bugs_found = true;
@@ -238,8 +230,9 @@ BeesHashTable::prefetch_loop()
 					// Count these instead of calculating the number so we get better stats in case of exceptions
 					occupied_count += this_bucket_occupied_count;
 				}
+				lock.unlock();
 				if (duplicate_bugs_found) {
-					set_extent_dirty_locked(ext);
+					set_extent_dirty(ext);
 				}
 			});
 		}
@@ -282,10 +275,9 @@ BeesHashTable::prefetch_loop()
 
 		graph_blob << "Now:     " << format_time(time(NULL)) << "\n";
 		graph_blob << "Uptime:  " << m_ctx->total_timer().age() << " seconds\n";
-		graph_blob << "Version: " << BEES_VERSION << "\n";
 
-		graph_blob
-			<< "\nHash table page occupancy histogram (" << occupied_count << "/" << total_count << " cells occupied, " << (occupied_count * 100 / total_count) << "%)\n"
+		graph_blob 
+			<< "\nHash table page occupancy histogram (" << occupied_count << "/" << total_count << " cells occupied, " << (occupied_count * 100 / total_count) << "%)\n" 
 			<< out.str() << "0%      |      25%      |      50%      |      75%      |   100% page fill\n"
 			<< "compressed " << compressed_count << " (" << percent(compressed_count, occupied_count) << ")"
 			<< " new-style " << compressed_offset_count << " (" << percent(compressed_offset_count, occupied_count) << ")"
@@ -314,70 +306,56 @@ BeesHashTable::prefetch_loop()
 	}
 }
 
-size_t
-BeesHashTable::hash_to_extent_index(HashType hash)
-{
-	auto pr = get_extent_range(hash);
-	uint64_t extent_index = reinterpret_cast<const Extent *>(pr.first) - m_extent_ptr;
-	THROW_CHECK2(runtime_error, extent_index, m_extents, extent_index < m_extents);
-	return extent_index;
-}
-
-BeesHashTable::ExtentMetaData::ExtentMetaData() :
-	m_mutex_ptr(make_shared<mutex>())
-{
-}
-
-unique_lock<mutex>
-BeesHashTable::lock_extent_by_index(uint64_t extent_index)
-{
-	THROW_CHECK2(out_of_range, extent_index, m_extents, extent_index < m_extents);
-	return unique_lock<mutex>(*m_extent_metadata.at(extent_index).m_mutex_ptr);
-}
-
-unique_lock<mutex>
-BeesHashTable::lock_extent_by_hash(HashType hash)
+void
+BeesHashTable::fetch_missing_extent(HashType hash)
 {
 	BEESTOOLONG("fetch_missing_extent for hash " << to_hex(hash));
-	return lock_extent_by_index(hash_to_extent_index(hash));
-}
+	if (using_shared_map()) return;
+	THROW_CHECK1(runtime_error, m_buckets, m_buckets > 0);
+	auto pr = get_extent_range(hash);
+	uint64_t extent_number = reinterpret_cast<Extent *>(pr.first) - m_extent_ptr;
+	THROW_CHECK1(runtime_error, extent_number, extent_number < m_extents);
 
-void
-BeesHashTable::fetch_missing_extent_by_index(uint64_t extent_index)
-{
-	BEESNOTE("checking hash extent #" << extent_index << " of " << m_extents << " extents");
-	auto lock = lock_extent_by_index(extent_index);
-	if (!m_extent_metadata.at(extent_index).m_missing) {
+	unique_lock<mutex> lock(m_extent_mutex);
+	if (!m_buckets_missing.count(extent_number)) {
 		return;
 	}
 
+	size_t missing_buckets = m_buckets_missing.size();
+	lock.unlock();
+
+	BEESNOTE("fetch waiting for hash extent #" << extent_number << ", " << missing_buckets << " left to fetch");
+
+	// Acquire blocking lock on this extent only
+	LockSet<uint64_t>::Lock extent_lock(m_extent_lock_set, extent_number);
+
+	// Check missing again because someone else might have fetched this
+	// extent for us while we didn't hold any locks
+	lock.lock();
+	if (!m_buckets_missing.count(extent_number)) {
+		BEESCOUNT(hash_extent_in_twice);
+		return;
+	}
+	lock.unlock();
+
 	// OK we have to read this extent
-	BEESNOTE("fetching hash extent #" << extent_index << " of " << m_extents << " extents");
-	BEESTRACE("Fetching hash extent #" << extent_index << " of " << m_extents << " extents");
-	BEESTOOLONG("Fetching hash extent #" << extent_index << " of " << m_extents << " extents");
+	BEESNOTE("fetching hash extent #" << extent_number << ", " << missing_buckets << " left to fetch");
 
-	uint8_t *dirty_extent     = m_extent_ptr[extent_index].p_byte;
-	uint8_t *dirty_extent_end = m_extent_ptr[extent_index + 1].p_byte;
+	BEESTRACE("Fetching missing hash extent " << extent_number);
+	uint8_t *dirty_extent     = m_extent_ptr[extent_number].p_byte;
+	uint8_t *dirty_extent_end = m_extent_ptr[extent_number + 1].p_byte;
 
-	// If the read fails don't retry, just go with whatever data we have
-	m_extent_metadata.at(extent_index).m_missing = false;
-
-	catch_all([&]() {
+	{
 		BEESTOOLONG("pread(fd " << m_fd << " '" << name_fd(m_fd)<< "', length " << to_hex(dirty_extent_end - dirty_extent) << ", offset " << to_hex(dirty_extent - m_byte_ptr) << ")");
 		pread_or_die(m_fd, dirty_extent, dirty_extent_end - dirty_extent, dirty_extent - m_byte_ptr);
-	});
+	}
 
-	// Only count extents successfully read
 	BEESCOUNT(hash_extent_in);
-}
-
-void
-BeesHashTable::fetch_missing_extent_by_hash(HashType hash)
-{
-	uint64_t extent_index = hash_to_extent_index(hash);
-	BEESNOTE("waiting to fetch hash extent #" << extent_index << " of " << m_extents << " extents");
-
-	fetch_missing_extent_by_index(extent_index);
+	// We don't block when fetching an extent but we do slow down the
+	// prefetch thread.
+	m_prefetch_rate_limit.borrow(BLOCK_SIZE_HASHTAB_EXTENT);
+	lock.lock();
+	m_buckets_missing.erase(extent_number);
 }
 
 bool
@@ -399,10 +377,10 @@ BeesHashTable::find_cell(HashType hash)
 		rv.push_back(toxic_cell);
 		return rv;
 	}
-	fetch_missing_extent_by_hash(hash);
+	fetch_missing_extent(hash);
 	BEESTOOLONG("find_cell hash " << BeesHash(hash));
 	vector<Cell> rv;
-	auto lock = lock_extent_by_hash(hash);
+	unique_lock<mutex> lock(m_bucket_mutex);
 	auto er = get_cell_range(hash);
 	// FIXME:  Weed out zero addresses in the table due to earlier bugs
 	copy_if(er.first, er.second, back_inserter(rv), [=](const Cell &ip) { return ip.e_hash == hash && ip.e_addr >= 0x1000; });
@@ -418,9 +396,10 @@ BeesHashTable::find_cell(HashType hash)
 void
 BeesHashTable::erase_hash_addr(HashType hash, AddrType addr)
 {
-	fetch_missing_extent_by_hash(hash);
+	// if (m_shared) return;
+	fetch_missing_extent(hash);
 	BEESTOOLONG("erase hash " << to_hex(hash) << " addr " << addr);
-	auto lock = lock_extent_by_hash(hash);
+	unique_lock<mutex> lock(m_bucket_mutex);
 	auto er = get_cell_range(hash);
 	Cell mv(hash, addr);
 	Cell *ip = find(er.first, er.second, mv);
@@ -428,7 +407,7 @@ BeesHashTable::erase_hash_addr(HashType hash, AddrType addr)
 	if (found) {
 		// Lookups on invalid addresses really hurt us.  Kill it with fire!
 		*ip = Cell(0, 0);
-		set_extent_dirty_locked(hash_to_extent_index(hash));
+		set_extent_dirty(hash);
 		BEESCOUNT(hash_erase);
 #if 0
 		if (verify_cell_range(er.first, er.second)) {
@@ -446,9 +425,9 @@ BeesHashTable::erase_hash_addr(HashType hash, AddrType addr)
 bool
 BeesHashTable::push_front_hash_addr(HashType hash, AddrType addr)
 {
-	fetch_missing_extent_by_hash(hash);
+	fetch_missing_extent(hash);
 	BEESTOOLONG("push_front_hash_addr hash " << BeesHash(hash) <<" addr " << BeesAddress(addr));
-	auto lock = lock_extent_by_hash(hash);
+	unique_lock<mutex> lock(m_bucket_mutex);
 	auto er = get_cell_range(hash);
 	Cell mv(hash, addr);
 	Cell *ip = find(er.first, er.second, mv);
@@ -478,7 +457,7 @@ BeesHashTable::push_front_hash_addr(HashType hash, AddrType addr)
 	// There is now a space at the front, insert there if different
 	if (er.first[0] != mv) {
 		er.first[0] = mv;
-		set_extent_dirty_locked(hash_to_extent_index(hash));
+		set_extent_dirty(hash);
 		BEESCOUNT(hash_front);
 	}
 #if 0
@@ -497,9 +476,9 @@ BeesHashTable::push_front_hash_addr(HashType hash, AddrType addr)
 bool
 BeesHashTable::push_random_hash_addr(HashType hash, AddrType addr)
 {
-	fetch_missing_extent_by_hash(hash);
+	fetch_missing_extent(hash);
 	BEESTOOLONG("push_random_hash_addr hash " << BeesHash(hash) << " addr " << BeesAddress(addr));
-	auto lock = lock_extent_by_hash(hash);
+	unique_lock<mutex> lock(m_bucket_mutex);
 	auto er = get_cell_range(hash);
 	Cell mv(hash, addr);
 	Cell *ip = find(er.first, er.second, mv);
@@ -562,14 +541,14 @@ BeesHashTable::push_random_hash_addr(HashType hash, AddrType addr)
 	case_cond = 5;
 ret_dirty:
 	BEESCOUNT(hash_insert);
-	set_extent_dirty_locked(hash_to_extent_index(hash));
+	set_extent_dirty(hash);
 ret:
 #if 0
 	if (verify_cell_range(er.first, er.second, false)) {
 		BEESLOG("while push_randoming (case " << case_cond << ") pos " << pos
 			<< " ip " << (ip - er.first) << " " << mv);
-		// dump_bucket_locked(saved.data(), saved.data() + saved.size());
-		// dump_bucket_locked(er.first, er.second);
+		// dump_bucket(saved.data(), saved.data() + saved.size());
+		// dump_bucket(er.first, er.second);
 	}
 #else
 	(void)case_cond;
@@ -595,36 +574,12 @@ BeesHashTable::try_mmap_flags(int flags)
 }
 
 void
-BeesHashTable::open_file()
+BeesHashTable::set_shared(bool shared)
 {
-	// OK open hash table
-	BEESNOTE("opening hash table '" << m_filename << "' target size " << m_size << " (" << pretty(m_size) << ")");
-
-	// Try to open existing hash table
-	Fd new_fd = openat(m_ctx->home_fd(), m_filename.c_str(), FLAGS_OPEN_FILE_RW, 0700);
-
-	// If that doesn't work, try to make a new one
-	if (!new_fd) {
-		string tmp_filename = m_filename + ".tmp";
-		BEESLOGNOTE("creating new hash table '" << tmp_filename << "'");
-		unlinkat(m_ctx->home_fd(), tmp_filename.c_str(), 0);
-		new_fd = openat_or_die(m_ctx->home_fd(), tmp_filename, FLAGS_CREATE_FILE, 0700);
-		BEESLOGNOTE("truncating new hash table '" << tmp_filename << "' size " << m_size << " (" << pretty(m_size) << ")");
-		ftruncate_or_die(new_fd, m_size);
-		BEESLOGNOTE("truncating new hash table '" << tmp_filename << "' -> '" << m_filename << "'");
-		renameat_or_die(m_ctx->home_fd(), tmp_filename, m_ctx->home_fd(), m_filename);
-	}
-
-	Stat st(new_fd);
-	off_t new_size = st.st_size;
-
-	THROW_CHECK1(invalid_argument, new_size, new_size > 0);
-	THROW_CHECK1(invalid_argument, new_size, (new_size % BLOCK_SIZE_HASHTAB_EXTENT) == 0);
-	m_size = new_size;
-	m_fd = new_fd;
+	m_shared = shared;
 }
 
-BeesHashTable::BeesHashTable(shared_ptr<BeesContext> ctx, string filename, off_t size) :
+BeesHashTable::BeesHashTable(shared_ptr<BeesContext> ctx, string filename) :
 	m_ctx(ctx),
 	m_size(0),
 	m_void_ptr(nullptr),
@@ -632,29 +587,35 @@ BeesHashTable::BeesHashTable(shared_ptr<BeesContext> ctx, string filename, off_t
 	m_buckets(0),
 	m_cells(0),
 	m_writeback_thread("hash_writeback"),
-	m_prefetch_thread("hash_prefetch"),
+	m_prefetch_thread("hash_prefetch " + m_ctx->root_path()),
 	m_flush_rate_limit(BEES_FLUSH_RATE),
+	m_prefetch_rate_limit(BEES_FLUSH_RATE),
 	m_stats_file(m_ctx->home_fd(), "beesstats.txt")
 {
-	// Sanity checks to protect the implementation from its weaknesses
+	BEESNOTE("opening hash table " << filename);
+
+	m_fd = openat_or_die(m_ctx->home_fd(), filename, FLAGS_OPEN_FILE_RW, 0700);
+	Stat st(m_fd);
+	m_size = st.st_size;
+
+	BEESTRACE("hash table size " << m_size);
+	BEESTRACE("hash table bucket size " << BLOCK_SIZE_HASHTAB_BUCKET);
+	BEESTRACE("hash table extent size " << BLOCK_SIZE_HASHTAB_EXTENT);
+
 	THROW_CHECK2(invalid_argument, BLOCK_SIZE_HASHTAB_BUCKET, BLOCK_SIZE_HASHTAB_EXTENT, (BLOCK_SIZE_HASHTAB_EXTENT % BLOCK_SIZE_HASHTAB_BUCKET) == 0);
 
+	// Does the union work?
+	THROW_CHECK2(runtime_error, m_void_ptr, m_cell_ptr, m_void_ptr == m_cell_ptr);
+	THROW_CHECK2(runtime_error, m_void_ptr, m_byte_ptr, m_void_ptr == m_byte_ptr);
+	THROW_CHECK2(runtime_error, m_void_ptr, m_bucket_ptr, m_void_ptr == m_bucket_ptr);
+	THROW_CHECK2(runtime_error, m_void_ptr, m_extent_ptr, m_void_ptr == m_extent_ptr);
+
 	// There's more than one union
 	THROW_CHECK2(runtime_error, sizeof(Bucket), BLOCK_SIZE_HASHTAB_BUCKET, BLOCK_SIZE_HASHTAB_BUCKET == sizeof(Bucket));
 	THROW_CHECK2(runtime_error, sizeof(Bucket::p_byte), BLOCK_SIZE_HASHTAB_BUCKET, BLOCK_SIZE_HASHTAB_BUCKET == sizeof(Bucket::p_byte));
 	THROW_CHECK2(runtime_error, sizeof(Extent), BLOCK_SIZE_HASHTAB_EXTENT, BLOCK_SIZE_HASHTAB_EXTENT == sizeof(Extent));
 	THROW_CHECK2(runtime_error, sizeof(Extent::p_byte), BLOCK_SIZE_HASHTAB_EXTENT, BLOCK_SIZE_HASHTAB_EXTENT == sizeof(Extent::p_byte));
 
-	m_filename = filename;
-	m_size = size;
-	open_file();
-
-	// Now we know size we can compute stuff
-
-	BEESTRACE("hash table size " << m_size);
-	BEESTRACE("hash table bucket size " << BLOCK_SIZE_HASHTAB_BUCKET);
-	BEESTRACE("hash table extent size " << BLOCK_SIZE_HASHTAB_EXTENT);
-
 	BEESLOG("opened hash table filename '" << filename << "' length " << m_size);
 	m_buckets = m_size / BLOCK_SIZE_HASHTAB_BUCKET;
 	m_cells = m_buckets * c_cells_per_bucket;
@@ -663,38 +624,29 @@ BeesHashTable::BeesHashTable(shared_ptr<BeesContext> ctx, string filename, off_t
 
 	BEESLOG("\tflush rate limit " << BEES_FLUSH_RATE);
 
-	// Try to mmap that much memory
-	try_mmap_flags(MAP_PRIVATE | MAP_ANONYMOUS);
+	if (using_shared_map()) {
+		try_mmap_flags(MAP_SHARED);
+	} else {
+		try_mmap_flags(MAP_PRIVATE | MAP_ANONYMOUS);
+	}
 
 	if (!m_cell_ptr) {
-		THROW_ERRNO("unable to mmap " << filename);
+		THROW_ERROR(runtime_error, "unable to mmap " << filename);
 	}
 
-	// Do unions work the way we think (and rely on)?
-	THROW_CHECK2(runtime_error, m_void_ptr, m_cell_ptr, m_void_ptr == m_cell_ptr);
-	THROW_CHECK2(runtime_error, m_void_ptr, m_byte_ptr, m_void_ptr == m_byte_ptr);
-	THROW_CHECK2(runtime_error, m_void_ptr, m_bucket_ptr, m_void_ptr == m_bucket_ptr);
-	THROW_CHECK2(runtime_error, m_void_ptr, m_extent_ptr, m_void_ptr == m_extent_ptr);
-
-	// Give all the madvise hints that the kernel understands
-	const struct madv_flag {
-		const char *name;
-		int value;
-	} madv_flags[] = {
-		{ .name = "MADV_HUGEPAGE", .value = MADV_HUGEPAGE },
-		{ .name = "MADV_DONTFORK", .value = MADV_DONTFORK },
-		{ .name = "MADV_DONTDUMP", .value = MADV_DONTDUMP },
-		{ .name = "", .value = 0 },
-	};
-	for (auto fp = madv_flags; fp->value; ++fp) {
-		BEESTOOLONG("madvise(" << fp->name << ")");
-		if (madvise(m_byte_ptr, m_size, fp->value)) {
-			BEESLOG("madvise(..., " << fp->name << "): " << strerror(errno) << " (ignored)");
+	if (!using_shared_map()) {
+		// madvise fails if MAP_SHARED
+		if (using_any_madvise()) {
+			// DONTFORK because we sometimes do fork,
+			// but the child doesn't touch any of the many, many pages
+			BEESTOOLONG("madvise(MADV_HUGEPAGE | MADV_DONTFORK)");
+			DIE_IF_NON_ZERO(madvise(m_byte_ptr, m_size, MADV_HUGEPAGE | MADV_DONTFORK));
+		}
+		for (uint64_t i = 0; i < m_size / sizeof(Extent); ++i) {
+			m_buckets_missing.insert(i);
 		}
 	}
 
-	m_extent_metadata.resize(m_extents);
-
 	m_writeback_thread.exec([&]() {
 		writeback_loop();
         });

src/bees-resolve.cc

@@ -105,7 +105,7 @@ BeesResolver::adjust_offset(const BeesFileRange &haystack, const BeesBlockData &
 	bool is_legacy = false;
 	if (m_addr.is_compressed()) {
 		BtrfsExtentWalker ew(haystack.fd(), haystack.begin(), m_ctx->root_fd());
-		BEESTRACE("haystack extent data " << ew);
+		BEESTRACE("haystack extent data " << ew); 
 		Extent e = ew.current();
 		if (m_addr.has_compressed_offset()) {
 			off_t coff = m_addr.get_compressed_offset();
@@ -196,7 +196,7 @@ BeesResolver::chase_extent_ref(const BtrfsInodeOffsetRoot &bior, BeesBlockData &
 
 	Fd file_fd = m_ctx->roots()->open_root_ino(bior.m_root, bior.m_inum);
 	if (!file_fd) {
-		// Deleted snapshots generate craptons of these
+		// Delete snapshots generate craptons of these
 		// BEESINFO("No FD in chase_extent_ref " << bior);
 		BEESCOUNT(chase_no_fd);
 		return BeesFileRange();
@@ -378,10 +378,7 @@ BeesResolver::for_each_extent_ref(BeesBlockData bbd, function<bool(const BeesFil
 				// We have reliable block addresses now, so we guarantee we can hit the desired block.
 				// Failure in chase_extent_ref means we are done, and don't need to look up all the
 				// other references.
-				// Or...not?  If we have a compressed extent, some refs will not match
-				// if there is are two references to the same extent with a reference
-				// to a different extent between them.
-				// stop_now = true;
+				stop_now = true;
 			}
 		});
 
@@ -480,6 +477,11 @@ BeesResolver::find_all_matches(BeesBlockData &bbd)
 bool
 BeesResolver::operator<(const BeesResolver &that) const
 {
-	// Lowest count, highest address
-	return tie(that.m_bior_count, m_addr) < tie(m_bior_count, that.m_addr);
+	if (that.m_bior_count < m_bior_count) {
+		return true;
+	} else if (m_bior_count < that.m_bior_count) {
+		return false;
+	}
+	return m_addr < that.m_addr;
 }
+

src/bees-roots.cc

@@ -1,14 +1,11 @@
 #include "bees.h"
 
 #include "crucible/cache.h"
-#include "crucible/process.h"
 #include "crucible/string.h"
 
 #include <fstream>
 #include <tuple>
 
-#include <inttypes.h>
-
 using namespace crucible;
 using namespace std;
 
@@ -45,26 +42,17 @@ BeesCrawlState::BeesCrawlState() :
 bool
 BeesCrawlState::operator<(const BeesCrawlState &that) const
 {
-	return tie(m_objectid, m_offset, m_root, m_min_transid, m_max_transid)
-		< tie(that.m_objectid, that.m_offset, that.m_root, that.m_min_transid, that.m_max_transid);
+	return tie(m_root, m_objectid, m_offset, m_min_transid, m_max_transid)
+		< tie(that.m_root, that.m_objectid, that.m_offset, that.m_min_transid, that.m_max_transid);
 }
 
 string
 BeesRoots::crawl_state_filename() const
 {
 	string rv;
-
-	// Legacy filename included UUID
 	rv += "beescrawl.";
 	rv += m_ctx->root_uuid();
 	rv += ".dat";
-
-	struct stat buf;
-	if (fstatat(m_ctx->home_fd(), rv.c_str(), &buf, AT_SYMLINK_NOFOLLOW)) {
-		// Use new filename
-		rv = "beescrawl.dat";
-	}
-
 	return rv;
 }
 
@@ -113,12 +101,6 @@ BeesRoots::state_save()
 
 	m_crawl_state_file.write(ofs.str());
 
-	// Renaming things is hard after release
-	if (m_crawl_state_file.name() != "beescrawl.dat") {
-		renameat(m_ctx->home_fd(), m_crawl_state_file.name().c_str(), m_ctx->home_fd(), "beescrawl.dat");
-		m_crawl_state_file.name("beescrawl.dat");
-	}
-
 	BEESNOTE("relocking crawl state");
 	lock.lock();
 	// Not really correct but probably close enough
@@ -153,12 +135,9 @@ BeesRoots::crawl_state_erase(const BeesCrawlState &bcs)
 		return;
 	}
 
-	auto found = m_root_crawl_map.find(bcs.m_root);
-	if (found != m_root_crawl_map.end()) {
-		auto hold_this_until_unlocked = found->second;
-		m_root_crawl_map.erase(found);
+	if (m_root_crawl_map.count(bcs.m_root)) {
+		m_root_crawl_map.erase(bcs.m_root);
 		m_crawl_dirty = true;
-		lock.unlock();
 	}
 }
 
@@ -180,9 +159,9 @@ BeesRoots::transid_min()
 uint64_t
 BeesRoots::transid_max()
 {
+	BEESNOTE("Calculating transid_max");
 	uint64_t rv = 0;
 	uint64_t root = 0;
-	BEESNOTE("Calculating transid_max (" << rv << " as of root " << root << ")");
 	BEESTRACE("Calculating transid_max...");
 	do {
 		root = next_root(root);
@@ -197,12 +176,76 @@ BeesRoots::transid_max()
 	return rv;
 }
 
+void
+BeesRoots::crawl_roots()
+{
+	BEESNOTE("Crawling roots");
+
+	unique_lock<mutex> lock(m_mutex);
+	if (m_root_crawl_map.empty()) {
+		BEESNOTE("idle, crawl map is empty");
+		m_condvar.wait(lock);
+		// Don't count the time we were waiting as part of the crawl time
+		m_crawl_timer.reset();
+	}
+
+	// Work from a copy because BeesCrawl might change the world under us
+	auto crawl_map_copy = m_root_crawl_map;
+	lock.unlock();
+
+	BeesFileRange first_range;
+	shared_ptr<BeesCrawl> first_crawl;
+	for (auto i : crawl_map_copy) {
+		auto this_crawl = i.second;
+		auto this_range = this_crawl->peek_front();
+		if (this_range) {
+			auto tuple_this = make_tuple(this_range.fid().ino(), this_range.fid().root(), this_range.begin());
+			auto tuple_first = make_tuple(first_range.fid().ino(), first_range.fid().root(), first_range.begin());
+			if (!first_range || tuple_this < tuple_first) {
+				first_crawl = this_crawl;
+				first_range = this_range;
+			}
+		}
+	}
+
+	if (first_range) {
+		catch_all([&]() {
+			// BEESINFO("scan_forward " << first_range);
+			m_ctx->scan_forward(first_range);
+		});
+		BEESCOUNT(crawl_scan);
+		m_crawl_current = first_crawl->get_state();
+		auto first_range_popped = first_crawl->pop_front();
+		THROW_CHECK2(runtime_error, first_range, first_range_popped, first_range == first_range_popped);
+		return;
+	}
+
+	BEESLOG("Crawl ran out of data after " << m_crawl_timer.lap() << "s, waiting for more...");
+	BEESCOUNT(crawl_done);
+	BEESNOTE("idle, waiting for more data");
+	lock.lock();
+	m_condvar.wait(lock);
+
+	// Don't count the time we were waiting as part of the crawl time
+	m_crawl_timer.reset();
+}
+
+void
+BeesRoots::crawl_thread()
+{
+	BEESNOTE("crawling");
+	while (1) {
+		catch_all([&]() {
+			crawl_roots();
+		});
+	}
+}
+
 void
 BeesRoots::writeback_thread()
 {
-	while (true) {
-		// BEESNOTE(m_crawl_current << (m_crawl_dirty ? " (dirty)" : ""));
-		BEESNOTE((m_crawl_dirty ? "dirty" : "clean") << ", interval " << BEES_WRITEBACK_INTERVAL << "s");
+	while (1) {
+		BEESNOTE(m_crawl_current << (m_crawl_dirty ? " (dirty)" : ""));
 
 		catch_all([&]() {
 			BEESNOTE("saving crawler state");
@@ -300,16 +343,17 @@ BeesRoots::state_load()
 BeesRoots::BeesRoots(shared_ptr<BeesContext> ctx) :
 	m_ctx(ctx),
 	m_crawl_state_file(ctx->home_fd(), crawl_state_filename()),
-	m_writeback_thread("crawl_writeback")
+	m_crawl_thread("crawl " + ctx->root_path()),
+	m_writeback_thread("crawl_writeback " + ctx->root_path())
 {
-	// This is a sanity check to prevent us from running out of FDs
-	m_lock_set.max_size(BEES_WORKER_THREAD_LIMIT);
-
-	catch_all([&]() {
-		state_load();
-	});
-	m_writeback_thread.exec([&]() {
-		writeback_thread();
+	m_crawl_thread.exec([&]() {
+		catch_all([&]() {
+			state_load();
+		});
+		m_writeback_thread.exec([&]() {
+			writeback_thread();
+		});
+		crawl_thread();
 	});
 }
 
@@ -390,7 +434,7 @@ BeesRoots::open_root_nocache(uint64_t rootid)
 				THROW_CHECK2(runtime_error, new_root_id, rootid, new_root_id == rootid);
 				Stat st(rv);
 				THROW_CHECK1(runtime_error, st.st_ino, st.st_ino == BTRFS_FIRST_FREE_OBJECTID);
-				// BEESINFO("open_root_nocache " << rootid << ": " << name_fd(rv));
+				BEESINFO("open_root_nocache " << rootid << ": " << name_fd(rv));
 				return rv;
 			}
 		}
@@ -514,27 +558,6 @@ BeesRoots::open_root_ino_nocache(uint64_t root, uint64_t ino)
 			break;
 		}
 
-		// As of 4.12 the kernel rejects dedup requests with
-		// src and dst that have different datasum flags.
-		//
-		// We can't detect those from userspace reliably, but
-		// we can detect the common case where one file is
-		// marked with the nodatasum (which implies nodatacow)
-		// on a filesystem that is mounted with datacow.
-		// These are arguably out of scope for dedup.
-		//
-		// To fix this properly, we have to keep track of which
-		// pairs of inodes failed to dedup, guess that the reason
-		// for failure was a mismatch of datasum flags, and
-		// create temporary files with the right flags somehow.
-		int attr = ioctl_iflags_get(rv);
-		if (attr & FS_NOCOW_FL) {
-			BEESLOG("Opening " << name_fd(rv) << " found FS_NOCOW_FL flag in " << to_hex(attr));
-			rv = Fd();
-			BEESCOUNT(open_wrong_flags);
-			break;
-		}
-
 		BEESTRACE("mapped " << BeesFileId(root, ino));
 		BEESTRACE("\tto " << name_fd(rv));
 		BEESCOUNT(open_hit);
@@ -553,54 +576,8 @@ BeesRoots::open_root_ino(uint64_t root, uint64_t ino)
 
 BeesCrawl::BeesCrawl(shared_ptr<BeesContext> ctx, BeesCrawlState initial_state) :
 	m_ctx(ctx),
-	m_state(initial_state),
-	m_thread(astringprintf("crawl_%" PRIu64, m_state.m_root))
+	m_state(initial_state)
 {
-	m_thread.exec([&]() {
-		crawl_thread();
-	});
-}
-
-BeesCrawl::~BeesCrawl()
-{
-	BEESLOGNOTE("Stopping crawl thread " << m_state);
-	unique_lock<mutex> lock(m_mutex);
-	m_stopped = true;
-	m_cond_stopped.notify_all();
-	lock.unlock();
-	BEESLOGNOTE("Joining crawl thread " << m_state);
-	m_thread.join();
-	BEESLOG("Stopped crawl thread " << m_state);
-}
-
-void
-BeesCrawl::crawl_thread()
-{
-	Timer crawl_timer;
-	while (!m_stopped) {
-		BEESNOTE("pop_front " << m_state);
-		auto this_range = pop_front();
-		if (this_range) {
-			catch_all([&]() {
-				BEESNOTE("waiting for scan thread limit " << m_state);
-				auto crawl_lock = m_ctx->roots()->lock_set().make_lock(m_state.m_root);
-
-				BEESNOTE("scan_forward " << this_range);
-				m_ctx->scan_forward(this_range);
-			});
-			BEESCOUNT(crawl_scan);
-		} else {
-			auto crawl_time = crawl_timer.age();
-			BEESLOGNOTE("Crawl ran out of data after " << crawl_time << "s, waiting for more...");
-			unique_lock<mutex> lock(m_mutex);
-			if (m_stopped) {
-				break;
-			}
-			m_cond_stopped.wait_for(lock, chrono::duration<double>(BEES_COMMIT_INTERVAL));
-			crawl_timer.reset();
-		}
-	}
-	BEESLOG("Crawl thread stopped");
 }
 
 bool
@@ -648,11 +625,11 @@ BeesCrawl::fetch_extents()
 	}
 
 	BEESNOTE("crawling " << get_state());
-	// BEESLOG("Crawling " << get_state());
+	BEESLOG("Crawling " << get_state());
 
 	Timer crawl_timer;
 
-	BtrfsIoctlSearchKey sk(BEES_MAX_CRAWL_SIZE * (sizeof(btrfs_file_extent_item) + sizeof(btrfs_ioctl_search_header)));
+	BtrfsIoctlSearchKey sk;
 	sk.tree_id = old_state.m_root;
 	sk.min_objectid = old_state.m_objectid;
 	sk.min_type = sk.max_type = BTRFS_EXTENT_DATA_KEY;
@@ -667,16 +644,9 @@ BeesCrawl::fetch_extents()
 	BEESTRACE("Searching crawl sk " << static_cast<btrfs_ioctl_search_key&>(sk));
 	bool ioctl_ok = false;
 	{
-#if 0
-		BEESNOTE("waiting to search crawl sk " << static_cast<btrfs_ioctl_search_key&>(sk));
-		auto lock = bees_ioctl_lock_set.make_lock(gettid());
-#endif
-
 		BEESNOTE("searching crawl sk " << static_cast<btrfs_ioctl_search_key&>(sk));
 		BEESTOOLONG("Searching crawl sk " << static_cast<btrfs_ioctl_search_key&>(sk));
-		Timer crawl_timer;
 		ioctl_ok = sk.do_ioctl_nothrow(m_ctx->root_fd());
-		BEESCOUNTADD(crawl_ms, crawl_timer.age() * 1000);
 	}
 
 	if (ioctl_ok) {
@@ -692,7 +662,7 @@ BeesCrawl::fetch_extents()
 		return next_transid();
 	}
 
-	// BEESLOG("Crawling " << sk.m_result.size() << " results from " << get_state());
+	BEESLOG("Crawling " << sk.m_result.size() << " results from " << get_state());
 	auto results_left = sk.m_result.size();
 	BEESNOTE("crawling " << results_left << " results from " << get_state());
 	size_t count_other = 0;
@@ -709,6 +679,7 @@ BeesCrawl::fetch_extents()
 
 		BEESTRACE("i = " << i);
 
+#if 1
 		// We need the "+ 1" and objectid rollover that next_min does.
 		auto new_state = get_state();
 		new_state.m_objectid = sk.min_objectid;
@@ -720,6 +691,7 @@ BeesCrawl::fetch_extents()
 		// is a lot of metadata we can't process.  Favor forward
 		// progress over losing search results.
 		set_state(new_state);
+#endif
 
 		// Ignore things that aren't EXTENT_DATA_KEY
 		if (i.type != BTRFS_EXTENT_DATA_KEY) {
@@ -732,24 +704,13 @@ BeesCrawl::fetch_extents()
 		if (gen < get_state().m_min_transid) {
 			BEESCOUNT(crawl_gen_low);
 			++count_low;
-			// We want (need?) to scan these anyway?
-			// The header generation refers to the transid
-			// of the metadata page holding the current ref.
-			// This includes anything else in that page that
-			// happened to be modified, regardless of how
-			// old it is.
-			// The file_extent_generation refers to the
-			// transid of the extent item's page, which is
-			// a different approximation of what we want.
-			// Combine both of these filters to minimize
-			// the number of times we unnecessarily re-read
-			// an extent.
-			continue;
+			// We probably want (need?) to scan these anyway.
+			// continue;
 		}
 		if (gen > get_state().m_max_transid) {
 			BEESCOUNT(crawl_gen_high);
 			++count_high;
-			// This shouldn't ever happen...and so far, doesn't.
+			// This shouldn't ever happen
 			// continue;
 		}
 
@@ -769,7 +730,6 @@ BeesCrawl::fetch_extents()
 				break;
 			case BTRFS_FILE_EXTENT_PREALLOC:
 				BEESCOUNT(crawl_prealloc);
-				// fallthrough
 			case BTRFS_FILE_EXTENT_REG: {
 				auto physical = call_btrfs_get(btrfs_stack_file_extent_disk_bytenr, i.m_data);
 				auto ram = call_btrfs_get(btrfs_stack_file_extent_ram_bytes, i.m_data);
@@ -799,7 +759,7 @@ BeesCrawl::fetch_extents()
 			}
 		}
 	}
-	// BEESLOG("Crawled inline " << count_inline << " data " << count_data << " other " << count_other << " unknown " << count_unknown << " gen_low " << count_low << " gen_high " << count_high << " " << get_state() << " in " << crawl_timer << "s");
+	BEESLOG("Crawled inline " << count_inline << " data " << count_data << " other " << count_other << " unknown " << count_unknown << " gen_low " << count_low << " gen_high " << count_high << " " << get_state() << " in " << crawl_timer << "s");
 
 	return true;
 }
@@ -824,8 +784,7 @@ BeesCrawl::peek_front()
 	if (m_extents.empty()) {
 		return BeesFileRange();
 	}
-	auto rv = *m_extents.begin();
-	return rv;
+	return *m_extents.begin();
 }
 
 BeesFileRange
@@ -838,6 +797,12 @@ BeesCrawl::pop_front()
 	}
 	auto rv = *m_extents.begin();
 	m_extents.erase(m_extents.begin());
+#if 0
+	auto state = get_state();
+	state.m_objectid = rv.fid().ino();
+	state.m_offset = rv.begin();
+	set_state(state);
+#endif
 	return rv;
 }
 
@@ -845,8 +810,7 @@ BeesCrawlState
 BeesCrawl::get_state()
 {
 	unique_lock<mutex> lock(m_state_mutex);
-	auto rv = m_state;
-	return rv;
+	return m_state;
 }
 
 void

src/bees-types.cc

@@ -71,18 +71,7 @@ operator<<(ostream &os, const BeesFileRange &bfr)
 	if (bfr.end() == numeric_limits<off_t>::max()) {
 		os << "- [" << to_hex(bfr.begin()) << "..eof]";
 	} else {
-		os << pretty(bfr.size()) << " ";
-		if (bfr.begin() != 0) {
-			os << "[" << to_hex(bfr.begin());
-		} else {
-			os << "(";
-		}
-		os << ".." << to_hex(bfr.end());
-		if (!!bfr.m_fd && bfr.end() >= bfr.file_size()) {
-			os << ")";
-		} else {
-			os << "]";
-		}
+		os << pretty(bfr.size()) << " [" << to_hex(bfr.begin()) << ".." << to_hex(bfr.end()) << "]";
 	}
 	if (bfr.m_fid) {
 		os << " fid = " << bfr.m_fid;
@@ -103,6 +92,8 @@ operator<<(ostream &os, const BeesRangePair &brp)
 		<< "\ndst = " << brp.second.fd() << " " << name_fd(brp.second.fd());
 }
 
+mutex BeesFileRange::s_mutex;
+
 bool
 BeesFileRange::operator<(const BeesFileRange &that) const
 {
@@ -154,6 +145,7 @@ off_t
 BeesFileRange::file_size() const
 {
 	if (m_file_size <= 0) {
+		// Use method fd() not member m_fd() so we hold lock
 		Stat st(fd());
 		m_file_size = st.st_size;
 		// These checks could trigger on valid input, but that would mean we have
@@ -186,21 +178,31 @@ BeesFileRange::grow_begin(off_t delta)
 BeesFileRange::BeesFileRange(const BeesBlockData &bbd) :
 	m_fd(bbd.fd()),
 	m_begin(bbd.begin()),
-	m_end(bbd.end())
+	m_end(bbd.end()),
+	m_file_size(-1)
 {
 }
 
 BeesFileRange::BeesFileRange(Fd fd, off_t begin, off_t end) :
 	m_fd(fd),
 	m_begin(begin),
-	m_end(end)
+	m_end(end),
+	m_file_size(-1)
 {
 }
 
 BeesFileRange::BeesFileRange(const BeesFileId &fid, off_t begin, off_t end) :
 	m_fid(fid),
 	m_begin(begin),
-	m_end(end)
+	m_end(end),
+	m_file_size(-1)
+{
+}
+
+BeesFileRange::BeesFileRange() :
+	m_begin(0),
+	m_end(0),
+	m_file_size(-1)
 {
 }
 
@@ -283,18 +285,22 @@ BeesFileRange::operator BeesBlockData() const
 Fd
 BeesFileRange::fd() const
 {
+	unique_lock<mutex> lock(s_mutex);
 	return m_fd;
 }
 
 Fd
 BeesFileRange::fd(const shared_ptr<BeesContext> &ctx) const
 {
+	unique_lock<mutex> lock(s_mutex);
 	// If we don't have a fid we can't do much here
 	if (m_fid) {
 		if (!m_fd) {
 			// If we don't have a fd, open by fid
 			if (m_fid && ctx) {
+				lock.unlock();
 				Fd new_fd = ctx->roots()->open_root_ino(m_fid);
+				lock.lock();
 				m_fd = new_fd;
 			}
 		} else {
@@ -930,7 +936,6 @@ BeesBlockData::data() const
 {
 	if (m_data.empty()) {
 		THROW_CHECK1(invalid_argument, size(), size() > 0);
-		BEESNOTE("Reading BeesBlockData " << *this);
 		BEESTOOLONG("Reading BeesBlockData " << *this);
 		Timer read_timer;
 

src/bees.cc

@@ -1,5 +1,6 @@
 #include "bees.h"
 
+#include "crucible/interp.h"
 #include "crucible/limits.h"
 #include "crucible/process.h"
 #include "crucible/string.h"
@@ -19,37 +20,27 @@
 #include <linux/fs.h>
 #include <sys/ioctl.h>
 
-// setrlimit
-#include <sys/time.h>
-#include <sys/resource.h>
-
-#include <getopt.h>
-
 using namespace crucible;
 using namespace std;
 
 int
-do_cmd_help(char *argv[])
+do_cmd_help(const ArgList &argv)
 {
-	cerr << "Usage: " << argv[0] << " [options] fs-root-path [fs-root-path-2...]\n"
+	cerr << "Usage: " << argv[0] << " fs-root-path [fs-root-path-2...]\n"
 		"Performs best-effort extent-same deduplication on btrfs.\n"
 		"\n"
 		"fs-root-path MUST be the root of a btrfs filesystem tree (id 5).\n"
 		"Other directories will be rejected.\n"
 		"\n"
-		"Options:\n"
-		"\t-h, --help\t\tShow this help\n"
-		"\t-t, --timestamps\tShow timestamps in log output (default)\n"
-		"\t-T, --notimestamps\tOmit timestamps in log output\n"
-		"\t-p, --absolute-paths\tShow absolute paths (default)\n"
-		"\t-P, --relative-paths\tShow paths relative to $CWD\n"
+		"Multiple filesystems can share a single hash table (BEESHOME)\n"
+		"but this only works well if the content of each filesystem\n"
+		"is distinct from all the others.\n"
+		"\n"
+		"Required environment variables:\n"
+		"\tBEESHOME\tPath to hash table and configuration files\n"
 		"\n"
 		"Optional environment variables:\n"
-		"\tBEESHOME\tPath to hash table and configuration files\n"
-		"\t\t\t(default is .beeshome/ in the root of each filesystem).\n"
-		"\n"
-		"\tBEESSTATUS\tFile to write status to (tmpfs recommended, e.g. /run).\n"
-		"\t\t\tNo status is written if this variable is unset.\n"
+		"\tBEESSTATUS\tFile to write status to (tmpfs recommended, e.g. /run)\n"
 		"\n"
 	<< endl;
 	return 0;
@@ -59,36 +50,30 @@ do_cmd_help(char *argv[])
 
 RateLimiter bees_info_rate_limit(BEES_INFO_RATE, BEES_INFO_BURST);
 
-thread_local BeesTracer *BeesTracer::tl_next_tracer = nullptr;
+thread_local BeesTracer *BeesTracer::s_next_tracer = nullptr;
 
 BeesTracer::~BeesTracer()
 {
 	if (uncaught_exception()) {
-		try {
-			m_func();
-		} catch (exception &e) {
-			BEESLOG("Nested exception: " << e.what());
-		} catch (...) {
-			BEESLOG("Nested exception ...");
-		}
+		m_func();
 		if (!m_next_tracer) {
 			BEESLOG("---  END  TRACE --- exception ---");
 		}
 	}
-	tl_next_tracer = m_next_tracer;
+	s_next_tracer = m_next_tracer;
 }
 
 BeesTracer::BeesTracer(function<void()> f) :
 	m_func(f)
 {
-	m_next_tracer = tl_next_tracer;
-	tl_next_tracer = this;
+	m_next_tracer = s_next_tracer;
+	s_next_tracer = this;
 }
 
 void
 BeesTracer::trace_now()
 {
-	BeesTracer *tp = tl_next_tracer;
+	BeesTracer *tp = s_next_tracer;
 	BEESLOG("--- BEGIN TRACE ---");
 	while (tp) {
 		tp->m_func();
@@ -97,17 +82,17 @@ BeesTracer::trace_now()
 	BEESLOG("---  END  TRACE ---");
 }
 
-thread_local BeesNote *BeesNote::tl_next = nullptr;
+thread_local BeesNote *BeesNote::s_next = nullptr;
 mutex BeesNote::s_mutex;
 map<pid_t, BeesNote*> BeesNote::s_status;
-thread_local string BeesNote::tl_name;
+thread_local string BeesNote::s_name;
 
 BeesNote::~BeesNote()
 {
-	tl_next = m_prev;
 	unique_lock<mutex> lock(s_mutex);
-	if (tl_next) {
-		s_status[gettid()] = tl_next;
+	s_next = m_prev;
+	if (s_next) {
+		s_status[gettid()] = s_next;
 	} else {
 		s_status.erase(gettid());
 	}
@@ -116,26 +101,28 @@ BeesNote::~BeesNote()
 BeesNote::BeesNote(function<void(ostream &os)> f) :
 	m_func(f)
 {
-	m_name = tl_name;
-	m_prev = tl_next;
-	tl_next = this;
 	unique_lock<mutex> lock(s_mutex);
-	s_status[gettid()] = tl_next;
+	m_name = s_name;
+	m_prev = s_next;
+	s_next = this;
+	s_status[gettid()] = s_next;
 }
 
 void
 BeesNote::set_name(const string &name)
 {
-	tl_name = name;
+	unique_lock<mutex> lock(s_mutex);
+	s_name = name;
 }
 
 string
 BeesNote::get_name()
 {
-	if (tl_name.empty()) {
+	unique_lock<mutex> lock(s_mutex);
+	if (s_name.empty()) {
 		return "bees";
 	} else {
-		return tl_name;
+		return s_name;
 	}
 }
 
@@ -217,21 +204,15 @@ operator<<(ostream &os, const BeesStatTmpl<T> &bs)
 
 // other ----------------------------------------
 
-/**
- * Don't allow two threads to use some btrfs ioctls at the same time.
- * Some of them consume egregious amounts of kernel CPU time and are
- * not interruptible, so if we have more threads than cores we will
- * effectively crash the kernel. */
-LockSet<pid_t> bees_ioctl_lock_set;
-
 template <class T>
 T&
 BeesStatTmpl<T>::at(string idx)
 {
-	if (!m_stats_map.count(idx)) {
+	unique_lock<mutex> lock(m_mutex);
+    if (!m_stats_map.count(idx)) {
 		m_stats_map[idx] = 0;
 	}
-	return m_stats_map[idx];
+    return m_stats_map[idx];
 }
 
 template <class T>
@@ -239,8 +220,7 @@ T
 BeesStatTmpl<T>::at(string idx) const
 {
 	unique_lock<mutex> lock(m_mutex);
-	auto rv = m_stats_map.at(idx);
-	return rv;
+    return m_stats_map.at(idx);
 }
 
 template <class T>
@@ -248,7 +228,7 @@ void
 BeesStatTmpl<T>::add_count(string idx, size_t amount)
 {
 	unique_lock<mutex> lock(m_mutex);
-	if (!m_stats_map.count(idx)) {
+    if (!m_stats_map.count(idx)) {
 		m_stats_map[idx] = 0;
 	}
 	m_stats_map.at(idx) += amount;
@@ -280,17 +260,14 @@ BeesStats
 BeesStats::operator-(const BeesStats &that) const
 {
 	if (&that == this) return BeesStats();
-
 	unique_lock<mutex> this_lock(m_mutex);
 	BeesStats this_copy;
 	this_copy.m_stats_map = m_stats_map;
-	this_lock.unlock();
-
 	unique_lock<mutex> that_lock(that.m_mutex);
 	BeesStats that_copy;
 	that_copy.m_stats_map = that.m_stats_map;
+	this_lock.unlock();
 	that_lock.unlock();
-
 	for (auto i : that.m_stats_map) {
 		if (i.second != 0) {
 			this_copy.at(i.first) -= i.second;
@@ -374,18 +351,6 @@ BeesStringFile::BeesStringFile(Fd dir_fd, string name, size_t limit) :
 	BEESLOG("BeesStringFile " << name_fd(m_dir_fd) << "/" << m_name << " max size " << pretty(m_limit));
 }
 
-void
-BeesStringFile::name(const string &new_name)
-{
-	m_name = new_name;
-}
-
-string
-BeesStringFile::name() const
-{
-	return m_name;
-}
-
 string
 BeesStringFile::read()
 {
@@ -419,13 +384,8 @@ BeesStringFile::write(string contents)
 		Fd ofd = openat_or_die(m_dir_fd, tmpname, FLAGS_CREATE_FILE, S_IRUSR | S_IWUSR);
 		BEESNOTE("writing " << tmpname << " in " << name_fd(m_dir_fd));
 		write_or_die(ofd, contents);
-#if 0
-		// This triggers too many btrfs bugs.  I wish I was kidding.
-		// Forget snapshots, balance, compression, and dedup:
-		// the system call you have to fear on btrfs is fsync().
 		BEESNOTE("fsyncing " << tmpname << " in " << name_fd(m_dir_fd));
 		DIE_IF_NON_ZERO(fsync(ofd));
-#endif
 	}
 	BEESNOTE("renaming " << tmpname << " to " << m_name << " in FD " << name_fd(m_dir_fd));
 	BEESTRACE("renaming " << tmpname << " to " << m_name << " in FD " << name_fd(m_dir_fd));
@@ -439,7 +399,6 @@ BeesTempFile::create()
 	BEESNOTE("creating temporary file in " << m_ctx->root_path());
 	BEESTOOLONG("creating temporary file in " << m_ctx->root_path());
 
-	Timer create_timer;
 	DIE_IF_MINUS_ONE(m_fd = openat(m_ctx->root_fd(), ".", FLAGS_OPEN_TMPFILE, S_IRUSR | S_IWUSR));
 	BEESCOUNT(tmp_create);
 
@@ -447,22 +406,18 @@ BeesTempFile::create()
 	// Resolves won't work there anyway.  There are lots of tempfiles
 	// and they're short-lived, so this ends up being just a memory leak
 	// m_ctx->blacklist_add(BeesFileId(m_fd));
-
-	// Put this inode in the cache so we can resolve it later
 	m_ctx->insert_root_ino(m_fd);
 
 	// Set compression attribute
-	BEESTRACE("Getting FS_COMPR_FL on m_fd " << name_fd(m_fd));
-	int flags = ioctl_iflags_get(m_fd);
+	int flags = 0;
+	BEESTRACE("Getting FS_COMPR_FL on m_fd " << name_fd(m_fd) << " flags " << to_hex(flags));
+	DIE_IF_MINUS_ONE(ioctl(m_fd, FS_IOC_GETFLAGS, &flags));
 	flags |= FS_COMPR_FL;
 	BEESTRACE("Setting FS_COMPR_FL on m_fd " << name_fd(m_fd) << " flags " << to_hex(flags));
-	ioctl_iflags_set(m_fd, flags);
+	DIE_IF_MINUS_ONE(ioctl(m_fd, FS_IOC_SETFLAGS, &flags));
 
 	// Always leave first block empty to avoid creating a file with an inline extent
 	m_end_offset = BLOCK_SIZE_CLONE;
-
-	// Count time spent here
-	BEESCOUNTADD(tmp_create_ms, create_timer.age() * 1000);
 }
 
 void
@@ -476,15 +431,11 @@ BeesTempFile::resize(off_t offset)
 	THROW_CHECK2(invalid_argument, m_end_offset, offset, m_end_offset < offset);
 
 	// Truncate
-	Timer resize_timer;
 	DIE_IF_NON_ZERO(ftruncate(m_fd, offset));
 	BEESCOUNT(tmp_resize);
 
 	// Success
 	m_end_offset = offset;
-
-	// Count time spent here
-	BEESCOUNTADD(tmp_resize_ms, resize_timer.age() * 1000);
 }
 
 BeesTempFile::BeesTempFile(shared_ptr<BeesContext> ctx) :
@@ -496,7 +447,7 @@ BeesTempFile::BeesTempFile(shared_ptr<BeesContext> ctx) :
 
 void
 BeesTempFile::realign()
-{
+{ 
 	if (m_end_offset > BLOCK_SIZE_MAX_TEMP_FILE) {
 		BEESLOG("temporary file size " << to_hex(m_end_offset) << " > max " << BLOCK_SIZE_MAX_TEMP_FILE);
 		BEESCOUNT(tmp_trunc);
@@ -538,13 +489,8 @@ BeesTempFile::make_copy(const BeesFileRange &src)
 
 	THROW_CHECK1(invalid_argument, src, src.size() > 0);
 
-	// FIEMAP used to give us garbage data, e.g. distinct adjacent
-	// extents merged into a single entry in the FIEMAP output.
-	// FIEMAP didn't stop giving us garbage data, we just stopped
-	// using FIEMAP.
-	// We shouldn't get absurdly large extents any more; however,
-	// it's still a problem if we do, so bail out and leave a trace
-	// in the log.
+	// FIXME:  don't know where these come from, but we can't handle them.
+	// Grab a trace for the log.
 	THROW_CHECK1(invalid_argument, src, src.size() < BLOCK_SIZE_MAX_TEMP_FILE);
 
 	realign();
@@ -553,7 +499,6 @@ BeesTempFile::make_copy(const BeesFileRange &src)
 	auto end = m_end_offset + src.size();
 	resize(end);
 
-	Timer copy_timer;
 	BeesFileRange rv(m_fd, begin, end);
 	BEESTRACE("copying to: " << rv);
 	BEESNOTE("copying " << src << " to " << rv);
@@ -579,30 +524,18 @@ BeesTempFile::make_copy(const BeesFileRange &src)
 		src_p += len;
 		dst_p += len;
 	}
-	BEESCOUNTADD(tmp_copy_ms, copy_timer.age() * 1000);
 
 	// We seem to get lockups without this!
 	if (did_block_write) {
-#if 1
-		// Is this fixed by "Btrfs: fix deadlock between dedup on same file and starting writeback"?
-		// No.
 		bees_sync(m_fd);
-#endif
 	}
 
 	BEESCOUNT(tmp_copy);
 	return rv;
 }
 
-unsigned
-bees_worker_thread_count()
-{
-	// Maybe # of cores * (scalar from 0.25..4)?
-	return max(1U, thread::hardware_concurrency() * 4);
-}
-
 int
-bees_main(int argc, char *argv[])
+bees_main(ArgList args)
 {
 	set_catch_explainer([&](string s) {
 		BEESLOG("\n\n*** EXCEPTION ***\n\t" << s << "\n***\n");
@@ -615,77 +548,12 @@ bees_main(int argc, char *argv[])
 	list<shared_ptr<BeesContext>> all_contexts;
 	shared_ptr<BeesContext> bc;
 
-	THROW_CHECK1(invalid_argument, argc, argc >= 0);
-
-	string cwd(readlink_or_die("/proc/self/cwd"));
-
-	// Defaults
-	bool chatter_prefix_timestamp = true;
-
-	// Parse options
-	int c;
-	while (1) {
-		int option_index = 0;
-		static struct option long_options[] = {
-			{ "timestamps",     no_argument, NULL, 't' },
-			{ "notimestamps",   no_argument, NULL, 'T' },
-			{ "absolute-paths", no_argument, NULL, 'p' },
-			{ "relative-paths", no_argument, NULL, 'P' },
-			{ "help",           no_argument, NULL, 'h' }
-		};
-
-		c = getopt_long(argc, argv, "TtPph", long_options, &option_index);
-		if (-1 == c) {
-			break;
-		}
-
-		switch (c) {
-			case 'T':
-				chatter_prefix_timestamp = false;
-				break;
-			case 't':
-				chatter_prefix_timestamp = true;
-				break;
-			case 'P':
-				crucible::set_relative_path(cwd);
-				break;
-			case 'p':
-				crucible::set_relative_path("");
-				break;
-			case 'h':
-				do_cmd_help(argv); // fallthrough
-			default:
-				return 2;
-		}
-	}
-
-	Chatter::enable_timestamp(chatter_prefix_timestamp);
-
-	if (!relative_path().empty()) {
-		BEESLOG("using relative path " << relative_path() << "\n");
-	}
-
-	// There can be only one because we measure running time with it
-	// EXPERIMENT:  don't try this on kernels before v4.14
-	// bees_ioctl_lock_set.max_size(1);
-
-	BEESLOG("setting rlimit NOFILE to " << BEES_OPEN_FILE_LIMIT);
-
-	struct rlimit lim = {
-		.rlim_cur = BEES_OPEN_FILE_LIMIT,
-		.rlim_max = BEES_OPEN_FILE_LIMIT,
-	};
-	int rv = setrlimit(RLIMIT_NOFILE, &lim);
-	if (rv) {
-		BEESLOG("setrlimit(RLIMIT_NOFILE, { " << lim.rlim_cur << " }): " << strerror(errno));
-	};
-
-	// Create a context and start crawlers
+	// Subscribe to fanotify events
 	bool did_subscription = false;
-	while (optind < argc) {
+	for (string arg : args) {
 		catch_all([&]() {
 			bc = make_shared<BeesContext>(bc);
-			bc->set_root_path(argv[optind++]);
+			bc->set_root_path(arg);
 			did_subscription = true;
 		});
 	}
@@ -706,18 +574,18 @@ bees_main(int argc, char *argv[])
 }
 
 int
-main(int argc, char *argv[])
+main(int argc, const char **argv)
 {
-	cerr << "bees version " << BEES_VERSION << endl;
-
 	if (argc < 2) {
 		do_cmd_help(argv);
 		return 2;
 	}
 
+	ArgList args(argv + 1);
+
 	int rv = 1;
 	catch_and_explain([&]() {
-		rv = bees_main(argc, argv);
+		rv = bees_main(args);
 	});
 	return rv;
 }

src/bees.h

@@ -1,6 +1,7 @@
 #ifndef BEES_H
 #define BEES_H
 
+#include "crucible/bool.h"
 #include "crucible/cache.h"
 #include "crucible/chatter.h"
 #include "crucible/error.h"
@@ -39,6 +40,13 @@ const off_t BLOCK_SIZE_MAX_EXTENT_SAME = 4096 * 4096;
 // Maximum length of a compressed extent in bytes
 const off_t BLOCK_SIZE_MAX_COMPRESSED_EXTENT = 128 * 1024;
 
+// Try to combine smaller extents into larger ones
+const off_t BLOCK_SIZE_MIN_EXTENT_DEFRAG = BLOCK_SIZE_MAX_COMPRESSED_EXTENT;
+
+// Avoid splitting extents that are already too small
+const off_t BLOCK_SIZE_MIN_EXTENT_SPLIT = BLOCK_SIZE_MAX_COMPRESSED_EXTENT;
+// const off_t BLOCK_SIZE_MIN_EXTENT_SPLIT = 1024LL * 1024 * 1024 * 1024;
+
 // Maximum length of any extent in bytes
 // except we've seen 1.03G extents...
 // ...FIEMAP is slow and full of lies
@@ -47,6 +55,8 @@ const off_t BLOCK_SIZE_MAX_EXTENT = 128 * 1024 * 1024;
 // Masks, so we don't have to write "(BLOCK_SIZE_CLONE - 1)" everywhere
 const off_t BLOCK_MASK_CLONE = BLOCK_SIZE_CLONE - 1;
 const off_t BLOCK_MASK_SUMS = BLOCK_SIZE_SUMS - 1;
+const off_t BLOCK_MASK_MMAP = BLOCK_SIZE_MMAP - 1;
+const off_t BLOCK_MASK_MAX_COMPRESSED_EXTENT = BLOCK_SIZE_MAX_COMPRESSED_EXTENT * 2 - 1;
 
 // Maximum temporary file size
 const off_t BLOCK_SIZE_MAX_TEMP_FILE = 1024 * 1024 * 1024;
@@ -60,43 +70,29 @@ const off_t BLOCK_SIZE_HASHTAB_EXTENT = 16 * 1024 * 1024;
 // Bytes per second we want to flush (8GB every two hours)
 const double BEES_FLUSH_RATE = 8.0 * 1024 * 1024 * 1024 / 7200.0;
 
-// How long we should wait for new btrfs transactions
-const double BEES_COMMIT_INTERVAL = 900;
-
-// Interval between writing non-hash-table things to disk, and starting new subvol crawlers
-const int BEES_WRITEBACK_INTERVAL = BEES_COMMIT_INTERVAL;
+// Interval between writing non-hash-table things to disk (15 minutes)
+const int BEES_WRITEBACK_INTERVAL = 900;
 
 // Statistics reports while scanning
 const int BEES_STATS_INTERVAL = 3600;
 
 // Progress shows instantaneous rates and thread status
-const int BEES_PROGRESS_INTERVAL = BEES_STATS_INTERVAL;
+const int BEES_PROGRESS_INTERVAL = 3600;
 
 // Status is output every freakin second.  Use a ramdisk.
 const int BEES_STATUS_INTERVAL = 1;
 
-// Number of file FDs to cache when not in active use
-const size_t BEES_FILE_FD_CACHE_SIZE = 4096;
-
-// Number of root FDs to cache when not in active use
-const size_t BEES_ROOT_FD_CACHE_SIZE = 1024;
-
-// Number of FDs to open (rlimit)
-const size_t BEES_OPEN_FILE_LIMIT = (BEES_FILE_FD_CACHE_SIZE + BEES_ROOT_FD_CACHE_SIZE) * 2 + 100;
-
-// Worker thread limit (more threads may be created, but only this number will be active concurrently)
-const size_t BEES_WORKER_THREAD_LIMIT = 128;
-
 // Log warnings when an operation takes too long
 const double BEES_TOO_LONG = 2.5;
 
 // Avoid any extent where LOGICAL_INO takes this long
-// const double BEES_TOXIC_DURATION = 9.9;
-// EXPERIMENT:  Kernel v4.14+ may let us ignore toxicity
-const double BEES_TOXIC_DURATION = BEES_COMMIT_INTERVAL;
+const double BEES_TOXIC_DURATION = 9.9;
+
+// How long we should wait for new btrfs transactions
+const double BEES_COMMIT_INTERVAL = 900;
 
 // How long between hash table histograms
-const double BEES_HASH_TABLE_ANALYZE_INTERVAL = BEES_STATS_INTERVAL;
+const double BEES_HASH_TABLE_ANALYZE_INTERVAL = 3600;
 
 // Rate limiting of informational messages
 const double BEES_INFO_RATE = 10.0;
@@ -106,7 +102,7 @@ const double BEES_INFO_BURST = 1.0;
 const size_t BEES_MAX_QUEUE_SIZE = 1024;
 
 // Read this many items at a time in SEARCHv2
-const size_t BEES_MAX_CRAWL_SIZE = 1024;
+const size_t BEES_MAX_CRAWL_SIZE = 4096;
 
 // If an extent has this many refs, pretend it does not exist
 // to avoid a crippling btrfs performance bug
@@ -140,8 +136,6 @@ const int FLAGS_OPEN_FANOTIFY = O_RDWR | O_NOATIME | O_CLOEXEC | O_LARGEFILE;
 	} \
 } while (0)
 
-#define BEESLOGNOTE(x) BEESLOG(x); BEESNOTE(x)
-
 #define BEESCOUNT(stat) do { \
 	BeesStats::s_global.add_count(#stat); \
 } while (0)
@@ -160,12 +154,12 @@ class BeesStatTmpl {
 	map<string, T>	m_stats_map;
 	mutable mutex	m_mutex;
 
-	T& at(string idx);
 public:
 	BeesStatTmpl() = default;
 	BeesStatTmpl(const BeesStatTmpl &that);
 	BeesStatTmpl &operator=(const BeesStatTmpl &that);
 	void add_count(string idx, size_t amount = 1);
+	T& at(string idx);
 	T at(string idx) const;
 
 friend ostream& operator<< <>(ostream &os, const BeesStatTmpl<T> &bs);
@@ -189,7 +183,7 @@ class BeesTracer {
 	function<void()> m_func;
 	BeesTracer *m_next_tracer = 0;
 	
-	thread_local static BeesTracer *tl_next_tracer;
+	thread_local static BeesTracer *s_next_tracer;
 public:
 	BeesTracer(function<void()> f);
 	~BeesTracer();
@@ -205,8 +199,8 @@ class BeesNote {
 	static mutex			s_mutex;
 	static map<pid_t, BeesNote*>	s_status;
 
-	thread_local static BeesNote	*tl_next;
-	thread_local static string	tl_name;
+	thread_local static BeesNote	*s_next;
+	thread_local static string	s_name;
 
 public:
 	BeesNote(function<void(ostream &)> f);
@@ -256,14 +250,15 @@ ostream& operator<<(ostream &os, const BeesFileId &bfi);
 
 class BeesFileRange {
 protected:
+	static mutex		s_mutex;
 	mutable Fd		m_fd;
 	mutable BeesFileId	m_fid;
-	off_t			m_begin = 0, m_end = 0;
-	mutable off_t		m_file_size = -1;
+	off_t			m_begin, m_end;
+	mutable off_t		m_file_size;
 
 public:
 
-	BeesFileRange() = default;
+	BeesFileRange();
 	BeesFileRange(Fd fd, off_t begin, off_t end);
 	BeesFileRange(const BeesFileId &fid, off_t begin, off_t end);
 	BeesFileRange(const BeesBlockData &bbd);
@@ -379,8 +374,6 @@ public:
 	BeesStringFile(Fd dir_fd, string name, size_t limit = 1024 * 1024);
 	string read();
 	void write(string contents);
-	void name(const string &new_name);
-	string name() const;
 };
 
 class BeesHashTable {
@@ -414,7 +407,7 @@ public:
 		uint8_t	p_byte[BLOCK_SIZE_HASHTAB_EXTENT];
 	} __attribute__((packed));
 
-	BeesHashTable(shared_ptr<BeesContext> ctx, string filename, off_t size = BLOCK_SIZE_HASHTAB_EXTENT);
+	BeesHashTable(shared_ptr<BeesContext> ctx, string filename);
 	~BeesHashTable();
 
 	vector<Cell>	find_cell(HashType hash);
@@ -422,6 +415,8 @@ public:
 	void		erase_hash_addr(HashType hash, AddrType addr);
 	bool		push_front_hash_addr(HashType hash, AddrType addr);
 
+	void		set_shared(bool shared);
+
 private:
 	string		m_filename;
 	Fd		m_fd;
@@ -443,41 +438,33 @@ private:
 	uint64_t		m_buckets;
 	uint64_t		m_extents;
 	uint64_t		m_cells;
+	set<uint64_t>		m_buckets_dirty;
+	set<uint64_t>		m_buckets_missing;
 	BeesThread  		m_writeback_thread;
 	BeesThread	        m_prefetch_thread;
 	RateLimiter		m_flush_rate_limit;
+	RateLimiter		m_prefetch_rate_limit;
+	mutex			m_extent_mutex;
+	mutex			m_bucket_mutex;
+	condition_variable	m_condvar;
 	set<HashType>		m_toxic_hashes;
 	BeesStringFile		m_stats_file;
 
-	// Mutex/condvar for the writeback thread
-	mutex			m_dirty_mutex;
-	condition_variable	m_dirty_condvar;
+	LockSet<uint64_t> 	m_extent_lock_set;
 
-	// Per-extent structures
-	struct ExtentMetaData {
-		shared_ptr<mutex> m_mutex_ptr;		// Access serializer
-		bool	m_dirty = false;	// Needs to be written back to disk
-		bool	m_missing = true;	// Needs to be read from disk
-		ExtentMetaData();
-	};
-	vector<ExtentMetaData>	m_extent_metadata;
+	DefaultBool		m_shared;
 
-	void open_file();
 	void writeback_loop();
 	void prefetch_loop();
 	void try_mmap_flags(int flags);
 	pair<Cell *, Cell *> get_cell_range(HashType hash);
 	pair<uint8_t *, uint8_t *> get_extent_range(HashType hash);
-	void fetch_missing_extent_by_hash(HashType hash);
-	void fetch_missing_extent_by_index(uint64_t extent_index);
-	void set_extent_dirty_locked(uint64_t extent_index);
+	void fetch_missing_extent(HashType hash);
+	void set_extent_dirty(HashType hash);
 	void flush_dirty_extents();
-	bool flush_dirty_extent(uint64_t extent_index);
 	bool is_toxic_hash(HashType h) const;
 
-	size_t			hash_to_extent_index(HashType ht);
-	unique_lock<mutex>	lock_extent_by_hash(HashType ht);
-	unique_lock<mutex>	lock_extent_by_index(uint64_t extent_index);
+	bool using_shared_map() const { return false; }
 
 	BeesHashTable(const BeesHashTable &) = delete;
 	BeesHashTable &operator=(const BeesHashTable &) = delete;
@@ -501,40 +488,35 @@ class BeesCrawl {
 
 	mutex					m_mutex;
 	set<BeesFileRange>			m_extents;
-	bool					m_deferred = false;
+	DefaultBool				m_deferred;
 
 	mutex					m_state_mutex;
 	BeesCrawlState				m_state;
 
-	BeesThread				m_thread;
-	bool					m_stopped = false;
-	condition_variable			m_cond_stopped;
-
 	bool fetch_extents();
 	void fetch_extents_harder();
 	bool next_transid();
 
 public:
-	~BeesCrawl();
 	BeesCrawl(shared_ptr<BeesContext> ctx, BeesCrawlState initial_state);
 	BeesFileRange peek_front();
 	BeesFileRange pop_front();
 	BeesCrawlState get_state();
 	void set_state(const BeesCrawlState &bcs);
-	void crawl_thread();
 };
 
 class BeesRoots {
 	shared_ptr<BeesContext>			m_ctx;
 
 	BeesStringFile				m_crawl_state_file;
+	BeesCrawlState				m_crawl_current;
 	map<uint64_t, shared_ptr<BeesCrawl>>	m_root_crawl_map;
 	mutex					m_mutex;
 	condition_variable			m_condvar;
-	bool					m_crawl_dirty = false;
+	DefaultBool				m_crawl_dirty;
 	Timer					m_crawl_timer;
+	BeesThread				m_crawl_thread;
 	BeesThread				m_writeback_thread;
-	LockSet<uint64_t>			m_lock_set;
 
 	void insert_new_crawl();
 	void insert_root(const BeesCrawlState &bcs);
@@ -549,6 +531,7 @@ class BeesRoots {
 	BeesCrawlState crawl_state_get(uint64_t root);
 	void crawl_state_set_dirty();
 	void crawl_state_erase(const BeesCrawlState &bcs);
+	void crawl_thread();
 	void writeback_thread();
 	uint64_t next_root(uint64_t root = 0);
 	void current_state_set(const BeesCrawlState &bcs);
@@ -561,7 +544,6 @@ public:
 	Fd open_root(uint64_t root);
 	Fd open_root_ino(uint64_t root, uint64_t ino);
 	Fd open_root_ino(const BeesFileId &bfi) { return open_root_ino(bfi.root(), bfi.ino()); }
-	LockSet<uint64_t> &lock_set() { return m_lock_set; }
 };
 
 struct BeesHash {
@@ -587,7 +569,7 @@ class BeesBlockData {
 	mutable BeesAddress	m_addr;
 	mutable Blob		m_data;
 	mutable BeesHash	m_hash;
-	mutable bool		m_hash_done = false;
+	mutable DefaultBool	m_hash_done;
 
 public:
 	// Constructor with the immutable fields
@@ -625,6 +607,42 @@ public:
 friend ostream & operator<<(ostream &os, const BeesRangePair &brp);
 };
 
+class BeesWorkQueueBase {
+	string 				m_name; 
+
+protected:
+	static mutex			s_mutex;
+	static set<BeesWorkQueueBase *>	s_all_workers;
+
+public:
+	virtual ~BeesWorkQueueBase();
+	BeesWorkQueueBase(const string &name);
+
+	string name() const;
+	void name(const string &new_name);
+
+	virtual size_t active_size() const = 0;
+	virtual list<string> peek_active(size_t count) const = 0;
+ 
+	static void for_each_work_queue(function<void(BeesWorkQueueBase *)> f);
+};
+
+template <class Task>
+class BeesWorkQueue : public BeesWorkQueueBase {
+	WorkQueue<Task>				m_active_queue;
+
+public:
+	BeesWorkQueue(const string &name);
+	~BeesWorkQueue();
+	void push_active(const Task &task, size_t limit);
+	void push_active(const Task &task);
+
+	size_t active_size() const override;
+	list<string> peek_active(size_t count) const override;
+
+	Task pop();
+};
+
 class BeesTempFile {
 	shared_ptr<BeesContext> m_ctx;
 	Fd			m_fd;
@@ -644,7 +662,6 @@ class BeesFdCache {
 	LRUCache<Fd, shared_ptr<BeesContext>, uint64_t>			m_root_cache;
 	LRUCache<Fd, shared_ptr<BeesContext>, uint64_t, uint64_t>	m_file_cache;
 	Timer								m_root_cache_timer;
-	Timer								m_file_cache_timer;
 
 public:
 	BeesFdCache();
@@ -656,7 +673,7 @@ public:
 struct BeesResolveAddrResult {
 	BeesResolveAddrResult();
 	vector<BtrfsInodeOffsetRoot> m_biors;
-	bool m_is_toxic = false;
+	DefaultBool m_is_toxic;
 	bool is_toxic() const { return m_is_toxic; }
 };
 
@@ -684,8 +701,6 @@ class BeesContext : public enable_shared_from_this<BeesContext> {
 
 	Timer						m_total_timer;
 
-	LockSet<uint64_t>			m_extent_lock_set;
-
 	void set_root_fd(Fd fd);
 
 	BeesResolveAddrResult resolve_addr_uncached(BeesAddress addr);
@@ -699,7 +714,7 @@ public:
 	void set_root_path(string path);
 
 	Fd root_fd() const { return m_root_fd; }
-	Fd home_fd();
+	Fd home_fd() const { return m_home_fd; }
 	string root_path() const { return m_root_path; }
 	string root_uuid() const { return m_root_uuid; }
 
@@ -723,7 +738,6 @@ public:
 	shared_ptr<BeesTempFile> tmpfile();
 
 	const Timer &total_timer() const { return m_total_timer; }
-	LockSet<uint64_t> &extent_lock_set() { return m_extent_lock_set; }
 
 	// TODO: move the rest of the FD cache methods here
 	void insert_root_ino(Fd fd);
@@ -737,22 +751,22 @@ class BeesResolver {
 	unsigned				m_bior_count;
 
 	// We found matching data, so we can dedup
-	bool					m_found_data = false;
+	DefaultBool				m_found_data;
 
 	// We found matching data, so we *did* dedup
-	bool					m_found_dup = false;
+	DefaultBool				m_found_dup;
 
 	// We found matching hash, so the hash table is still correct
-	bool					m_found_hash = false;
+	DefaultBool				m_found_hash;
 
 	// We found matching physical address, so the hash table isn't totally wrong
-	bool					m_found_addr = false;
+	DefaultBool				m_found_addr;
 
 	// We found matching physical address, but data did not match
-	bool					m_wrong_data = false;
+	DefaultBool				m_wrong_data;
 
 	// The whole thing is a placebo to avoid crippling btrfs performance bugs
-	bool					m_is_toxic = false;
+	DefaultBool				m_is_toxic;
 
 	BeesFileRange chase_extent_ref(const BtrfsInodeOffsetRoot &bior, BeesBlockData &needle_bbd);
 	BeesBlockData adjust_offset(const BeesFileRange &haystack, const BeesBlockData &needle);
@@ -806,12 +820,9 @@ public:
 };
 
 // And now, a giant pile of extern declarations
-extern const char *BEES_VERSION;
 string pretty(double d);
 extern RateLimiter bees_info_rate_limit;
 void bees_sync(int fd);
 string format_time(time_t t);
-extern LockSet<pid_t> bees_ioctl_lock_set;
-extern unsigned bees_worker_thread_count();
 
 #endif

src/fanotify-watch.cc

@@ -0,0 +1,91 @@
+#include <crucible/error.h>
+#include <crucible/fd.h>
+#include <crucible/ntoa.h>
+
+#include <iostream>
+#include <iomanip>
+#include <sstream>
+#include <string>
+
+#include <unistd.h>
+#include <sys/fanotify.h>
+
+using namespace crucible;
+using namespace std;
+
+static
+void
+usage(const char *name)
+{
+	cerr << "Usage: " << name << " directory" << endl;
+	cerr << "Reports fanotify events from directory" << endl;
+}
+
+struct fan_read_block {
+	struct fanotify_event_metadata fem;
+	// more here in the future.  Maybe.
+};
+
+static inline
+string
+fan_flag_ntoa(uint64_t ui)
+{
+	static const bits_ntoa_table flag_names[] = {
+		NTOA_TABLE_ENTRY_BITS(FAN_ACCESS),
+		NTOA_TABLE_ENTRY_BITS(FAN_OPEN),
+		NTOA_TABLE_ENTRY_BITS(FAN_MODIFY),
+		NTOA_TABLE_ENTRY_BITS(FAN_CLOSE),
+		NTOA_TABLE_ENTRY_BITS(FAN_CLOSE_WRITE),
+		NTOA_TABLE_ENTRY_BITS(FAN_CLOSE_NOWRITE),
+		NTOA_TABLE_ENTRY_BITS(FAN_Q_OVERFLOW),
+		NTOA_TABLE_ENTRY_BITS(FAN_ACCESS_PERM),
+		NTOA_TABLE_ENTRY_BITS(FAN_OPEN_PERM),
+		NTOA_TABLE_ENTRY_END()
+	};
+	return bits_ntoa(ui, flag_names);
+}
+
+int
+main(int argc, char **argv)
+{
+	if (argc < 1) {
+		usage(argv[0]);
+		exit(EXIT_FAILURE);
+	}
+
+	Fd fd;
+
+	DIE_IF_MINUS_ONE(fd = fanotify_init(FAN_CLASS_NOTIF, O_RDONLY | O_LARGEFILE | O_CLOEXEC | O_NOATIME));
+
+	for (char **argvp = argv + 1; *argvp; ++argvp) {
+		cerr << "fanotify_mark(" << *argvp << ")..." << flush;
+		DIE_IF_MINUS_ONE(fanotify_mark(fd, FAN_MARK_ADD | FAN_MARK_MOUNT, FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE | FAN_OPEN, FAN_NOFD, *argvp));
+		cerr << endl;
+	}
+
+	while (1) {
+		struct fan_read_block frb;
+		read_or_die(fd, frb);
+
+#if 0
+		cout << "event_len\t= " << frb.fem.event_len << endl;
+		cout << "vers\t= " << static_cast<int>(frb.fem.vers) << endl;
+		cout << "reserved\t= " << static_cast<int>(frb.fem.reserved) << endl;
+		cout << "metadata_len\t= " << frb.fem.metadata_len << endl;
+		cout << "mask\t= " << hex << frb.fem.mask << dec << "\t" << fan_flag_ntoa(frb.fem.mask) << endl;
+		cout << "fd\t= " << frb.fem.fd << endl;
+		cout << "pid\t= " << frb.fem.pid << endl;
+#endif
+
+		cout << "flags " << fan_flag_ntoa(frb.fem.mask) << " pid " << frb.fem.pid << ' ' << flush;
+
+		Fd event_fd(frb.fem.fd);
+		ostringstream oss;
+		oss << "/proc/self/fd/" << event_fd;
+		cout << "file " << readlink_or_die(oss.str()) << endl;
+
+		// cout << endl;
+	}
+	
+	return EXIT_SUCCESS;
+}

test/Makefile

@@ -1,7 +1,9 @@
 PROGRAMS = \
 	chatter \
 	crc64 \
+	execpipe \
 	fd \
+	interp \
 	limits \
 	path \
 	process \
@@ -19,7 +21,7 @@ LDFLAGS = -L../lib -Wl,-rpath=$(shell realpath ../lib)
 depends.mk: *.cc
 	for x in *.cc; do $(CXX) $(CXXFLAGS) -M "$$x"; done >> depends.mk.new
 	mv -fv depends.mk.new depends.mk
-
+                                       
 -include depends.mk
 
 %.o: %.cc %.h ../makeflags

test/crc64.cc

@@ -5,6 +5,18 @@
 
 using namespace crucible;
 
+static
+void
+test_getcrc64_strings()
+{
+	assert(Digest::CRC::crc64("John") == 5942451273432301568);
+	assert(Digest::CRC::crc64("Paul") == 5838402100630913024);
+	assert(Digest::CRC::crc64("George") == 6714394476893704192);
+	assert(Digest::CRC::crc64("Ringo") == 6038837226071130112);
+	assert(Digest::CRC::crc64("") == 0);
+	assert(Digest::CRC::crc64("\377\277\300\200") == 15615382887346470912ULL);
+}
+
 static
 void
 test_getcrc64_byte_arrays()
@@ -20,6 +32,7 @@ test_getcrc64_byte_arrays()
 int
 main(int, char**)
 {
+	RUN_A_TEST(test_getcrc64_strings());
 	RUN_A_TEST(test_getcrc64_byte_arrays());
 
 	exit(EXIT_SUCCESS);

test/execpipe.cc

@@ -0,0 +1,64 @@
+#include "tests.h"
+
+#include "crucible/execpipe.h"
+
+#include <ios>
+#include <cassert>
+#include <cstring>
+#include <cstdlib>
+#include <stdexcept>
+
+#include <unistd.h>
+
+using namespace crucible;
+using namespace std;
+
+#if 1 // Needs rework
+static inline
+void
+test_hello_world()
+{
+	// alarm(9);
+	Fd fd = popen([]() { return system("echo Hello, World!"); });
+	char buf[1024];
+	size_t rv = -1;
+	read_partial_or_die(fd, buf, rv);
+	assert(rv > 0);
+	string b(buf, buf + rv - 1);
+	// cerr << "hello_world says: '" << b << "'" << endl;
+	assert(b == "Hello, World!");
+}
+
+static inline
+void
+test_read_limit(size_t limit = 4096)
+{
+	alarm(9);
+	Fd fd = popen([]() { return system("yes Hello!"); });
+	try {
+		string b = read_all(fd, limit);
+	} catch (out_of_range &re) {
+		return;
+	}
+	assert(!"no exception thrown by read_all");
+}
+#endif
+
+namespace crucible {
+	extern bool assert_no_leaked_fds();
+};
+
+int
+main(int, char**)
+{
+#if 1
+	RUN_A_TEST(test_hello_world());
+	assert(assert_no_leaked_fds());
+	RUN_A_TEST(test_read_limit(4095));
+	RUN_A_TEST(test_read_limit(4096));
+	RUN_A_TEST(test_read_limit(4097));
+	assert(assert_no_leaked_fds());
+#endif
+
+	exit(EXIT_SUCCESS);
+}

test/interp.cc

@@ -0,0 +1,88 @@
+#include "tests.h"
+
+#include "crucible/interp.h"
+
+using namespace crucible;
+using namespace std;
+
+/***********************************************************************
+
+How this should work:
+
+Interpreter reads an arg list:
+
+	argv[0] --method0args --method1arg arg1 --method1arg=arg1 -- args...
+
+argv[0] should look up a shared_ptr<Command> which creates an object of
+type shared_ptr<Process>.  This object is used to receive args by
+method calls or one at a time.
+
+<Command> and <Process> can be the same object, or not.
+
+Process p methods:
+
+	p->spawn(Interp*) -> Process
+	p->exec(ArgList) -> Process / Result
+	p->method (from ArgParser<>)
+		p->finish() -> void (destroys object without early destruction warnings...?)
+		p->~Process() -> complains loudly if finish() not called first...?
+
+Result might be a pair of Process, string.  Or just string.
+
+ArgParser should be more like GetOpt:
+
+	build a dictionary and an arg list from arguments
+	Process methods should interrogate ArgParser
+	ArgParser might have a table of boolean and string option names so it can reject invalid options
+		but if it had that, we could also pass in Process and have it call methods on it
+		...but that is a _lot_ of pointer-hiding when we could KISS
+		...but if we had that solved, argparser tables look like lists of method names
+	ArgParser<T> has a table of names and methods on object of type T
+		ArgParser hides everything behind void* and hands off to a compiled implementation to do callbacks
+
+Extreme simplification:  arguments are themselves executable
+
+	so '--method_foo arg' really means construct MethodFoo(arg) and cast to shared_ptr<ProcArg>
+	then Process->invokeSomething(ProcArg)
+	too extreme, use argparser instead
+
+***********************************************************************/
+
+void
+test_arg_parser()
+{
+	ArgParser ap;
+	ArgList al( { "abc", "--def", "ghi" } );
+	ap.parse(NULL, al);
+}
+
+struct Thing {
+	int m_i;
+	double m_d;
+	string m_s;
+
+	void set_i(int i) { cerr << "i = " << i << endl; m_i = i; }
+	void set_d(double d) { cerr << "d = " << d << endl; m_d = d; }
+	void set_s(string s) { cerr << "s = " << s << endl; m_s = s; }
+};
+
+template <typename F, typename T, typename A>
+void
+assign(T& t, F f, A a)
+{
+	cerr << __PRETTY_FUNCTION__ << " - a = " << a << endl;
+	(t.*f)(a);
+}
+
+int
+main(int, char**)
+{
+	RUN_A_TEST(test_arg_parser());
+
+	Thing p;
+	assign(p, &Thing::set_i, 5);
+
+	cerr << "p.m_i = " << p.m_i << endl;
+
+	exit(EXIT_SUCCESS);
+}

test/limits.cc

@@ -141,13 +141,7 @@ test_cast_0x80000000_to_things()
 	SHOULD_FAIL(ranged_cast<unsigned short>(uv));
 	SHOULD_FAIL(ranged_cast<unsigned char>(uv));
 	SHOULD_PASS(ranged_cast<signed long long>(sv), sv);
-	if (sizeof(long) == 4) {
-		SHOULD_FAIL(ranged_cast<signed long>(sv));
-	} else if (sizeof(long) == 8) {
-		SHOULD_PASS(ranged_cast<signed long>(sv), sv);
-	} else {
-		assert(!"unhandled case, please add code for long here");
-	}
+	SHOULD_PASS(ranged_cast<signed long>(sv), sv);
 	SHOULD_FAIL(ranged_cast<signed short>(sv));
 	SHOULD_FAIL(ranged_cast<signed char>(sv));
 	if (sizeof(int) == 4) {
@@ -155,7 +149,7 @@ test_cast_0x80000000_to_things()
 	} else if (sizeof(int) == 8) {
 		SHOULD_PASS(ranged_cast<signed int>(sv), sv);
 	} else {
-		assert(!"unhandled case, please add code for int here");
+		assert(!"unhandled case, please add code here");
 	}
 }
 
@@ -180,13 +174,7 @@ test_cast_0xffffffff_to_things()
 	SHOULD_FAIL(ranged_cast<unsigned short>(uv));
 	SHOULD_FAIL(ranged_cast<unsigned char>(uv));
 	SHOULD_PASS(ranged_cast<signed long long>(sv), sv);
-	if (sizeof(long) == 4) {
-		SHOULD_FAIL(ranged_cast<signed long>(sv));
-	} else if (sizeof(long) == 8) {
-		SHOULD_PASS(ranged_cast<signed long>(sv), sv);
-	} else {
-		assert(!"unhandled case, please add code for long here");
-	}
+	SHOULD_PASS(ranged_cast<signed long>(sv), sv);
 	SHOULD_FAIL(ranged_cast<signed short>(sv));
 	SHOULD_FAIL(ranged_cast<signed char>(sv));
 	if (sizeof(int) == 4) {
@@ -194,7 +182,7 @@ test_cast_0xffffffff_to_things()
 	} else if (sizeof(int) == 8) {
 		SHOULD_PASS(ranged_cast<signed int>(sv), sv);
 	} else {
-		assert(!"unhandled case, please add code for int here");
+		assert(!"unhandled case, please add code here");
 	}
 }