You haven't mentioned what version of svn you use. As you say, there has been work recently --- some of it is in 1.7, some of it is on ^/subversion/branches/performance, some of it is on ^/subversion/branches/revprop-packing, and some additional ideas are in notes/fsfs-improvements.txt in trunk.
Ben Smith-Mannschott wrote on Mon, Sep 12, 2011 at 15:44:20 +0200: > I've made the observation that FSFS repositories perform better on > EXT4 than BTRFS. This probably isn't ground-breaking, but I thought > I'd share it. > > I've got two Linux machines: > > - colossus, using BTRFS spanned over two disks. > 2.6.38-11-generic #48-Ubuntu SMP Fri Jul 29 19:02:55 UTC 2011 > x86_64 x86_64 x86_64 GNU/Linux > > - oberon, using EXT4 on a 2-disk software RAID-1 set. > Linux oberon 2.6.32-33-generic #72-Ubuntu SMP Fri Jul 29 21:07:13 UTC 2011 > x86_64 GNU/Linux > > I've noticed that writes to FSFS repositories are 5x faster under EXT4 > than BTRFS. When svnsyncing form the same svn:// source to an local > repository (file://), oberon completes about 400 revisions in the time > it takes colossus to grind through 80. > > The BTRFS machine is our build server. Performance with (1.6.x) > working copies is quite acceptable, but I'm glad I'm not using it to > host svn repositories. > > Looks like the BTRFS people have some work to do. Maybe current > Kernels have already improved this picture. I know there has been > recent work on reducing the cost of meta-data operations (e.g. file > creation, ...) and that work is ongoing on defragmentation > functionality because of poor performance on files that are modified > in place heavily (e.g. sqlite). > > // ben
