On Thu, Nov 08, 2012 at 04:16:59PM -0600, Uri Moszkowicz wrote: > I ran "git cat-file commit some-tag" for every tag. They seem to be > roughly uniformly distributed between 0s and 2s and about 2/3 of the > time seems to be system. My disk is mounted over NFS so I tried on the > local disk and it didn't make a difference. > > I have only one 1.97GB pack. I ran "git gc --aggressive" before. Ah. NFS. That is almost certainly the source of the problem. Git will aggressively mmap. I would not be surprised to find that RHEL4's NFS implementation is not particularly fast at mmap-ing 2G files, and is spending a bunch of time in the kernel servicing the requests. Aside from upgrading your OS or getting off of NFS, I don't have a lot of advice. The performance characteristics you are seeing are so grossly off of what is normal that using git is probably going to be painful. Your 2s cat-files should be more like .002s. I don't think there's anything for git to fix here. You could try building with NO_MMAP, which will emulate it with pread. That might fare better under your NFS implementation. Or it might be just as bad. -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