On Tue, Jan 3, 2012 at 8:23 AM, Philip Martin <philip.mar...@wandisco.com> wrote: > Stefan Fuhrmann <stefanfuhrm...@alice-dsl.de> writes: > >> As of r1224839, FSFS now supports directory deltification. >> Please review the changes and run tests against different >> repositories so that we get a better idea of what the costs >> and benefits are. As soon as I'm back home, I will run tests >> against the Apache and KDE repositories. >> >> So far, I ran tests against the rather small TSVN repository. >> It seems that we get 50% more capacity / 33% size savings >> for 0 .. 20% CPU overhead. > > I've been testing this with the old CollabNet Subversion repository, the > first 40,515 Subversion revisions, on my Linux laptop: > > The db/revs directory (unpacked) is 320MB instead of 490MB. > Loading takes about 12% more CPU. > Dumping takes about 22% more CPU. > > which matches your results. Packing removes about 85MB for both > repositories. > > There are operations where reading the directory representations is more > dominant. 'svn log' on a path inside the repository uses 100% more CPU.
Is that peak CPU or overall? If the I/O overhead went down, I'd expect the peak CPU usage to go up, but the overall operation time to drop. (FWIW, I'm in the midst of loading a copy of the ASF repo using the new code, and I'll let folks know the results.) -Hyrum -- uberSVN: Apache Subversion Made Easy http://www.uberSVN.com/