path: root/t/perf/
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authorJeff King <>2016-08-22 22:01:10 (GMT)
committerJunio C Hamano <>2016-08-23 22:26:16 (GMT)
commitc7df68cbca75232f7843a7d70c58a0e98decef91 (patch)
treed02dcfd3708c53801ae43e5926b0496079c8a452 /t/perf/
parent8261e1f139db3f8aa6f9fd7d98c876cbeb0f927c (diff)
t/perf: add basic perf tests for delta base cache
This just shows off the improvements done by the last few patches, and gives us a baseline for noticing regressions in the future. Here are the results with linux.git as the perf "large repo": Test origin HEAD ------------------------------------------------------------------- 0003.1: log --raw 43.41(40.36+2.69) 33.86(30.96+2.41) -22.0% 0003.2: log -S 313.61(309.74+3.78) 298.75(295.58+3.00) -4.7% (for a large repo, the "log -S" improvements are greater if you bump the delta base cache limit, but I think it makes sense to test the "stock" behavior, since that is what most people will see). Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
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+test_description='Test operations that emphasize the delta base cache.
+We look at both "log --raw", which should put only trees into the delta cache,
+and "log -Sfoo --raw", which should look at both trees and blobs.
+Any effects will be emphasized if the test repository is fully packed (loose
+objects obviously do not use the delta base cache at all). It is also
+emphasized if the pack has long delta chains (e.g., as produced by "gc
+--aggressive"), though cache is still quite noticeable even with the default
+depth of 50.
+The setting of core.deltaBaseCacheLimit in the source repository is also
+relevant (depending on the size of your test repo), so be sure it is consistent
+between runs.
+. ./
+# puts mostly trees into the delta base cache
+test_perf 'log --raw' '
+ git log --raw >/dev/null
+test_perf 'log -S' '
+ git log --raw -Sfoo >/dev/null