From 27125b8140c3a367ef794ab4565ed27474ad7ee8 Mon Sep 17 00:00:00 2001 From: Zygo Blaxell Date: Sun, 28 Jan 2018 01:56:43 -0500 Subject: [PATCH] README: add scan-mode 2 and expand descriptions of modes 0 and 1 Signed-off-by: Zygo Blaxell --- README.md | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/README.md b/README.md index c620735..fa007bf 100644 --- a/README.md +++ b/README.md @@ -506,7 +506,12 @@ Command Line Options * Specify extent scanning algorithm. Default mode is 0. _EXPERIMENTAL_ feature that may go away. * Mode 0: scan extents in ascending order of (inode, subvol, offset). - * Mode 1: scan extents in round-robin order from each subvol. + Keeps shared extents between snapshots together. Reads files sequentially. + Minimizes temporary space usage. + * Mode 1: scan extents from all subvols in parallel. Good performance + on non-spinning media when subvols are unrelated. + * Mode 2: scan all extents from one subvol at a time. Good sequential + read performance for spinning media. Maximizes temporary space usage. * --timestamps (-t) * Enable timestamps in log output. * --notimestamps (-T)