761416ef91
Add performance tests to verify the performance of lookup table.
`p5310-pack-bitmaps.sh` contain tests with and without lookup table.
`p5312-pack-bitmaps-revs.sh` contain same tests with and without
lookup table but with `pack.writeReverseIndex` enabled.
Lookup table makes Git run faster in most of the cases. Below is the
result of `t/perf/p5310-pack-bitmaps.sh`.`perf/p5326-multi-pack-bitmaps.sh`
gives similar result. The repository used in the test is linux kernel.
Test this tree
-----------------------------------------------------------------------
5310.4: enable lookup table: false 0.01(0.00+0.00)
5310.5: repack to disk 320.89(230.20+23.45)
5310.6: simulated clone 14.04(5.78+1.79)
5310.7: simulated fetch 1.95(3.05+0.20)
5310.8: pack to file (bitmap) 44.73(20.55+7.45)
5310.9: rev-list (commits) 0.78(0.46+0.10)
5310.10: rev-list (objects) 4.07(3.97+0.08)
5310.11: rev-list with tag negated via --not 0.06(0.02+0.03)
--all (objects)
5310.12: rev-list with negative tag (objects) 0.21(0.15+0.05)
5310.13: rev-list count with blob:none 0.24(0.17+0.06)
5310.14: rev-list count with blob:limit=1k 7.07(5.92+0.48)
5310.15: rev-list count with tree:0 0.25(0.17+0.07)
5310.16: simulated partial clone 5.67(3.28+0.64)
5310.18: clone (partial bitmap) 16.05(8.34+1.86)
5310.19: pack to file (partial bitmap) 59.76(27.22+7.43)
5310.20: rev-list with tree filter (partial bitmap) 0.90(0.18+0.16)
5310.24: enable lookup table: true 0.01(0.00+0.00)
5310.25: repack to disk 319.73(229.30+23.01)
5310.26: simulated clone 13.69(5.72+1.78)
5310.27: simulated fetch 1.84(3.02+0.16)
5310.28: pack to file (bitmap) 45.63(20.67+7.50)
5310.29: rev-list (commits) 0.56(0.39+0.8)
5310.30: rev-list (objects) 3.77(3.74+0.08)
5310.31: rev-list with tag negated via --not 0.05(0.02+0.03)
--all (objects)
5310.32: rev-list with negative tag (objects) 0.21(0.15+0.05)
5310.33: rev-list count with blob:none 0.23(0.17+0.05)
5310.34: rev-list count with blob:limit=1k 6.65(5.72+0.40)
5310.35: rev-list count with tree:0 0.23(0.16+0.06)
5310.36: simulated partial clone 5.57(3.26+0.59)
5310.38: clone (partial bitmap) 15.89(8.39+1.84)
5310.39: pack to file (partial bitmap) 58.32(27.55+7.47)
5310.40: rev-list with tree filter (partial bitmap) 0.73(0.18+0.15)
Test 4-15 are tested without using lookup table. Same tests are
repeated in 16-30 (using lookup table).
Mentored-by: Taylor Blau <me@ttaylorr.com>
Co-Mentored-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com>
Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
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