On Sun, Apr 04, 2010 at 10:50:47AM -0400, Michael Poole wrote: > > Are you sure it doesn't subsequently speed up again? > > I have seen asymptotic slowdown as "git gc --aggressive" progresses on > certain repositories. It is particularly bad with > git://git.infradead.org/gcc.git (on an x86-64 system with 4 GB RAM). > git seemed to be thrashing swap badly as time went on. I don't know > that git gc --aggressive would *never* finish on my gcc-git repository. > I just know that it got to about 80% done in less than an hour, to 90% > after twelve hours, and about 94% after another twelve hours. (The same > operation on linux-2.6.git takes about 40 minutes with all the default > settings.) > > I may have been dreaming, but I thought with some 1.6.x version of git, > reducing core.packedGitLimit and pack.windowLimit (now windowMemory?) > mostly made the thrashing go away. When I try again with v1.7.0.2, > though, it doesn't seem to help very much -- there is still a lot of > swapping, and the git process got to about 7 GB virtual size before I > killed it after about 10 hours of operation. I packed Frans' sample kernel repo with "git gc --aggressive" last night. It did finish after about 9 hours. I didn't take memory usage measurements, but here's what time said: real 535m38.898s user 216m46.437s sys 0m24.186s That's 3.6 hours of CPU time over almost 9 hours (on a dual-core machine). The non-agressive pack was about 680M, and the result was 480M. The machine has 2G of RAM, and not much else running. So I would really not expect there to be much disk I/O required, but clearly we were waiting quite a bit. I'll try tweaking a few of the pack memory limits and try again. -Peff -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html