On Tue, Mar 18, 2014 at 12:00:48PM +0700, Duy Nguyen wrote: > On Tue, Mar 18, 2014 at 11:50 AM, Jeff King <peff@xxxxxxxx> wrote: > > On Sun, Mar 16, 2014 at 08:35:04PM +0700, Nguyễn Thái Ngọc Duy wrote: > > > >> As explained in the previous commit, current aggressive settings > >> --depth=250 --window=250 could slow down repository access > >> significantly. Notice that people usually work on recent history only, > >> we could keep recent history more loosely packed, so that repo access > >> is fast most of the time while the pack file remains small. > > > > One thing I have not seen is real-world timings showing the slowdown > > based on --depth. Did I miss them, or are we just making assumptions > > based on one old case from 2009 (that, AFAIK does not have real numbers, > > just speculation)? Has anyone measured the effect of bumping the delta > > cache size (and its hash implementation)? > > David tested it with git-blame [1]. I should probably run some tests > too (I don't remember if I tested some operations last time). > > http://thread.gmane.org/gmane.comp.version-control.git/242277/focus=242435 Ah, thanks. I do remember that thread now. It looks like David's last word is that he gets a significant performance from bumping the delta base cache size (and number of buckets). And that matches the timings I just did. I suspect there are still pathological cases that could behave worse, but it really sounds like we should be looking into improving that cache as a first step. -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