On Sat, Oct 07, 2017 at 03:12:08PM -0400, Derrick Stolee wrote: > In my local copy, I added a test to p4211-line-log.sh that runs "git log > --raw -r" and tested it on three copies of the Linux repo. In order, they > have 1 packfile (0 loose), 24 packfiles (0 loose), and 23 packfiles > (~324,000 loose). > > 4211.6: git log --raw -r 43.34(42.62+0.65) 40.47(40.16+0.27) -6.6% > 4211.6: git log --raw -r 88.77(86.54+2.12) 82.44(81.87+0.52) -7.1% > 4211.6: git log --raw -r 108.86(103.97+4.81) 103.92(100.63+3.19) -4.5% > > We have moderate performance gains for this command, despite the command > doing many more things than just checking abbreviations.
Yeah, while it's less exciting than seeing the 90% numbers for a micro-benchmark, I think this represents real-world gains (and 5-7% is nothing to sneeze at). You might also try adding "--format=%h" or --oneline to your invocation, which would compute abbreviations for each commit (making your workload more abbrev-heavy and possibly showing off the difference more). I also think "-r" isn't doing anything. Recursive diffs are the default for the "log" porcelain (even for --raw). > I plan to re-roll my patch on Monday including the following feedback items: > > * Remove test-list-objects and test-abbrev in favor of a new "git log" > performance test. > > * Fix binary search overflow error. > > * Check response from open_pack_index(p) in find_abbrev_len_for_pack(). > I plan to return without failure on non-zero result, which results in > no failure on a bad pack and the abbreviation length will be the > minimum required among all valid packs. (Thanks Stefan!) That all sounds reasonable to me. > - Teach 'cat-file' to --batch-check='%(objectsize:short)'. (Peff already > included a patch, perhaps that could be reviewed separately.) I think I'll let it lie in the list archive for now unless somebody has a real use case for it (though I'm tempted to add it purely for completionism, since it's so easy). -Peff
