On Wed, Apr 17, 2019 at 11:31:06AM +0100, [email protected] wrote: > From: Filipe Manana <[email protected]> > > Commit 41bd6067692382 ("Btrfs: fix fsync of files with multiple hard links > in new directories") introduced a path that makes fsync fallback to a full > transaction commit in order to avoid losing hard links and new ancestors > of the fsynced inode. That path is triggered only when the inode has more > than one hard link and either has a new hard link created in the current > transaction or the inode was evicted and reloaded in the current > transaction. > > That path ends up getting triggered very often (hundreds of times) during > the course of pgbench benchmarks, resulting in performance drops of about > 20%. > > This change restores the performance by not triggering the full transaction > commit in those cases, and instead iterate the fs/subvolume tree in search > of all possible new ancestors, for all hard links, to log them. > > Reported-by: Zhao Yuhu <[email protected]> > Tested-by: James Wang <[email protected]> > Signed-off-by: Filipe Manana <[email protected]>
Added to misc-next, thanks.
