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wed 2026-10-07 18:06 UTC

[PATCH v4 6/6] bitmap-lookup-table: add performance tests for lookup table

From
Abhradeep Chakraborty via GitGitGadget <gitgitgadget@gmail.com>
Date
Jul 20, 2022, 14:05 UTC
Message-ID
<52f7d8359ee766442ca03f0b47a491bcb2fab81b.1658325914.git.gitgitgadget@gmail.com>
In-Reply-To
<pull.1266.v4.git.1658325913.gitgitgadget@gmail.com>
From: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>

Add performance tests to verify the performance of lookup table with `pack.writeReverseIndex` enabled. This is to check the performance when the above configuration is set.

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: repack to disk (lookup=false)                   296.55(256.53+14.52)
5310.5: simulated clone                                 15.64(8.88+1.39)
5310.6: simulated fetch                                 1.65(2.75+0.20)
5310.7: pack to file (bitmap)                           48.71(30.20+7.58)
5310.8: rev-list (commits)                              0.61(0.41+0.08)
5310.9: rev-list (objects)                              4.38(4.26+0.09)
5310.10: rev-list with tag negated via --not            0.07(0.02+0.04)
         --all (objects)
5310.11: rev-list with negative tag (objects)           0.05(0.01+0.03)
5310.12: rev-list count with blob:none                  0.08(0.03+0.04)
5310.13: rev-list count with blob:limit=1k              7.29(6.92+0.30)
5310.14: rev-list count with tree:0                     0.08(0.03+0.04)
5310.15: simulated partial clone                        9.45(8.12+0.41)
5310.17: clone (partial bitmap)                         21.00(15.04+2.39)
5310.18: pack to file (partial bitmap)                  47.98(38.13+5.23)
5310.19: rev-list with tree filter (partial bitmap)     0.70(0.07+0.20)
5310.22: repack to disk (lookup=true)                   255.92(188.13+20.47)
5310.23: simulated clone                                13.78(8.84+1.09)
5310.24: simulated fetch                                0.52(0.63+0.14)
5310.25: pack to file (bitmap)                          44.34(28.94+6.84)
5310.26: rev-list (commits)                             0.48(0.31+0.06)
5310.27: rev-list (objects)                             4.02(3.93+0.07)
5310.28: rev-list with tag negated via --not            0.04(0.00+0.03)
         --all (objects)
5310.29: rev-list with negative tag (objects)           0.04(0.00+0.03)
5310.30: rev-list count with blob:none                  0.04(0.01+0.03)
5310.31: rev-list count with blob:limit=1k              6.48(6.23+0.22)
5310.32: rev-list count with tree:0                     0.04(0.01+0.03)
5310.33: simulated partial clone                        8.30(7.21+0.36)
5310.35: clone (partial bitmap)                         20.34(15.00+2.41)
5310.36: pack to file (partial bitmap)                  46.45(38.05+5.20)
5310.37: rev-list with tree filter (partial bitmap)     0.61(0.06+0.20)

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>
---
 t/perf/p5310-pack-bitmaps.sh       | 65 +++++++++++---------
 t/perf/p5326-multi-pack-bitmaps.sh | 95 +++++++++++++++++-------------
 2 files changed, 91 insertions(+), 69 deletions(-)
diff --git a/t/perf/p5310-pack-bitmaps.sh b/t/perf/p5310-pack-bitmaps.sh
index 6e8abcd5b21..adc753b6177 100755
--- a/t/perf/p5310-pack-bitmaps.sh
+++ b/t/perf/p5310-pack-bitmaps.sh
@@ -17,39 +17,50 @@ test_expect_success 'setup bitmap config' '
 	git config pack.writeReverseIndex true
 '
 
-# we need to create the tag up front such that it is covered by the repack and
-# thus by generated bitmaps.
-test_expect_success 'create tags' '
-	git tag --message="tag pointing to HEAD" perf-tag HEAD
-'
+test_bitmap () {
+	local enabled="$1"
 
-test_perf 'repack to disk' '
-	git repack -ad
-'
+	# we need to create the tag up front such that it is covered by the repack and
+	# thus by generated bitmaps.
+	test_expect_success 'create tags' '
+		git tag --message="tag pointing to HEAD" perf-tag HEAD
+	'
 
-test_full_bitmap
+	test_expect_success "use lookup table: $enabled" '
+		git config pack.writeBitmapLookupTable '"$enabled"'
+	'
 
-test_expect_success 'create partial bitmap state' '
-	# pick a commit to represent the repo tip in the past
-	cutoff=$(git rev-list HEAD~100 -1) &&
-	orig_tip=$(git rev-parse HEAD) &&
+	test_perf "repack to disk (lookup=$enabled)" '
+		git repack -ad
+	'
 
-	# now kill off all of the refs and pretend we had
-	# just the one tip
-	rm -rf .git/logs .git/refs/* .git/packed-refs &&
-	git update-ref HEAD $cutoff &&
+	test_full_bitmap
 
-	# and then repack, which will leave us with a nice
-	# big bitmap pack of the "old" history, and all of
-	# the new history will be loose, as if it had been pushed
-	# up incrementally and exploded via unpack-objects
-	git repack -Ad &&
+	test_expect_success "create partial bitmap state (lookup=$enabled)" '
+		# pick a commit to represent the repo tip in the past
+		cutoff=$(git rev-list HEAD~100 -1) &&
+		orig_tip=$(git rev-parse HEAD) &&
 
-	# and now restore our original tip, as if the pushes
-	# had happened
-	git update-ref HEAD $orig_tip
-'
+		# now kill off all of the refs and pretend we had
+		# just the one tip
+		rm -rf .git/logs .git/refs/* .git/packed-refs &&
+		git update-ref HEAD $cutoff &&
+
+		# and then repack, which will leave us with a nice
+		# big bitmap pack of the "old" history, and all of
+		# the new history will be loose, as if it had been pushed
+		# up incrementally and exploded via unpack-objects
+		git repack -Ad &&
+
+		# and now restore our original tip, as if the pushes
+		# had happened
+		git update-ref HEAD $orig_tip
+	'
+
+	test_partial_bitmap
+}
 
-test_partial_bitmap
+test_bitmap false
+test_bitmap true
 
 test_done
diff --git a/t/perf/p5326-multi-pack-bitmaps.sh b/t/perf/p5326-multi-pack-bitmaps.sh
index f2fa228f16a..1f4c7103529 100755
--- a/t/perf/p5326-multi-pack-bitmaps.sh
+++ b/t/perf/p5326-multi-pack-bitmaps.sh
@@ -6,47 +6,58 @@ test_description='Tests performance using midx bitmaps'
 
 test_perf_large_repo
 
-# we need to create the tag up front such that it is covered by the repack and
-# thus by generated bitmaps.
-test_expect_success 'create tags' '
-	git tag --message="tag pointing to HEAD" perf-tag HEAD
-'
-
-test_expect_success 'start with bitmapped pack' '
-	git repack -adb
-'
-
-test_perf 'setup multi-pack index' '
-	git multi-pack-index write --bitmap
-'
-
-test_expect_success 'drop pack bitmap' '
-	rm -f .git/objects/pack/pack-*.bitmap
-'
-
-test_full_bitmap
-
-test_expect_success 'create partial bitmap state' '
-	# pick a commit to represent the repo tip in the past
-	cutoff=$(git rev-list HEAD~100 -1) &&
-	orig_tip=$(git rev-parse HEAD) &&
-
-	# now pretend we have just one tip
-	rm -rf .git/logs .git/refs/* .git/packed-refs &&
-	git update-ref HEAD $cutoff &&
-
-	# and then repack, which will leave us with a nice
-	# big bitmap pack of the "old" history, and all of
-	# the new history will be loose, as if it had been pushed
-	# up incrementally and exploded via unpack-objects
-	git repack -Ad &&
-	git multi-pack-index write --bitmap &&
-
-	# and now restore our original tip, as if the pushes
-	# had happened
-	git update-ref HEAD $orig_tip
-'
-
-test_partial_bitmap
+test_bitmap () {
+	local enabled="$1"
+
+	# we need to create the tag up front such that it is covered by the repack and
+	# thus by generated bitmaps.
+	test_expect_success 'create tags' '
+		git tag --message="tag pointing to HEAD" perf-tag HEAD
+	'
+
+	test_expect_success "use lookup table: $enabled" '
+		git config pack.writeBitmapLookupTable '"$enabled"'
+	'
+
+	test_expect_success "start with bitmapped pack (lookup=$enabled)" '
+		git repack -adb
+	'
+
+	test_perf "setup multi-pack index (lookup=$enabled)" '
+		git multi-pack-index write --bitmap
+	'
+
+	test_expect_success "drop pack bitmap (lookup=$enabled)" '
+		rm -f .git/objects/pack/pack-*.bitmap
+	'
+
+	test_full_bitmap
+
+	test_expect_success "create partial bitmap state (lookup=$enabled)" '
+		# pick a commit to represent the repo tip in the past
+		cutoff=$(git rev-list HEAD~100 -1) &&
+		orig_tip=$(git rev-parse HEAD) &&
+
+		# now pretend we have just one tip
+		rm -rf .git/logs .git/refs/* .git/packed-refs &&
+		git update-ref HEAD $cutoff &&
+
+		# and then repack, which will leave us with a nice
+		# big bitmap pack of the "old" history, and all of
+		# the new history will be loose, as if it had been pushed
+		# up incrementally and exploded via unpack-objects
+		git repack -Ad &&
+		git multi-pack-index write --bitmap &&
+
+		# and now restore our original tip, as if the pushes
+		# had happened
+		git update-ref HEAD $orig_tip
+	'
+
+	test_partial_bitmap
+}
+
+test_bitmap false
+test_bitmap true
 
 test_done
-- 
gitgitgadget
Previous: Abhradeep Chakraborty via GitGitGadgetNext: Abhradeep Chakraborty via GitGitGadget
Message 109 of 162 in “Documentation/technical: describe bitmap lookup table extension”
  1. 1/6 Documentation/technical: describe bitmap lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jun 20, 2022
  2. 0/6 [GSoC] bitmap: integrate a lookup table extension to the bitmap formatAbhradeep Chakraborty via GitGitGadget, Jun 20, 2022
  3. 2/6 pack-bitmap: prepare to read lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jun 20, 2022
  4. 3/6 pack-bitmap-write.c: write lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jun 20, 2022
  5. 5/6 bitmap-commit-table: add tests for the bitmap lookup tableAbhradeep Chakraborty via GitGitGadget, Jun 20, 2022
  6. 4/6 builtin/pack-objects.c: learn pack.writeBitmapLookupTableTaylor Blau via GitGitGadget, Jun 20, 2022
  7. 6/6 bitmap-lookup-table: add performance testsAbhradeep Chakraborty via GitGitGadget, Jun 20, 2022
  8. Derrick StoleeJun 20, 2022
  9. Taylor BlauJun 20, 2022
  10. Taylor BlauJun 20, 2022
  11. Derrick StoleeJun 20, 2022
  12. Derrick StoleeJun 20, 2022
  13. Taylor BlauJun 20, 2022
  14. Taylor BlauJun 20, 2022
  15. Taylor BlauJun 20, 2022
  16. Abhradeep ChakrabortyJun 21, 2022
  17. Abhradeep ChakrabortyJun 21, 2022
  18. Abhradeep ChakrabortyJun 21, 2022
  19. Abhradeep ChakrabortyJun 21, 2022
  20. Abhradeep ChakrabortyJun 21, 2022
  21. Abhradeep ChakrabortyJun 21, 2022
  22. Abhradeep ChakrabortyJun 21, 2022
  23. Taylor BlauJun 22, 2022
  24. Taylor BlauJun 22, 2022
  25. Taylor BlauJun 22, 2022
  26. Abhradeep ChakrabortyJun 22, 2022
  27. Taylor BlauJun 22, 2022
  28. Taylor BlauJun 22, 2022
  29. Taylor BlauJun 22, 2022
  30. Taylor BlauJun 22, 2022
  31. Abhradeep ChakrabortyJun 22, 2022
  32. Taylor BlauJun 22, 2022
  33. 1/6 Documentation/technical: describe bitmap lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jun 26, 2022
  34. 2/6 pack-bitmap-write.c: write lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jun 26, 2022
  35. 3/6 pack-bitmap-write: learn pack.writeBitmapLookupTable and add testsAbhradeep Chakraborty via GitGitGadget, Jun 26, 2022
  36. 0/6 [GSoC] bitmap: integrate a lookup table extension to the bitmap formatAbhradeep Chakraborty via GitGitGadget, Jun 26, 2022
  37. 5/6 bitmap-lookup-table: add performance tests for lookup tableAbhradeep Chakraborty via GitGitGadget, Jun 26, 2022
  38. 6/6 p5310-pack-bitmaps.sh: enable pack.writeReverseIndex for testingAbhradeep Chakraborty via GitGitGadget, Jun 26, 2022
  39. 4/6 pack-bitmap: prepare to read lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jun 26, 2022
  40. Derrick StoleeJun 27, 2022
  41. Derrick StoleeJun 27, 2022
  42. Derrick StoleeJun 27, 2022
  43. Derrick StoleeJun 27, 2022
  44. Taylor BlauJun 27, 2022
  45. Taylor BlauJun 27, 2022
  46. Taylor BlauJun 27, 2022
  47. Abhradeep ChakrabortyJun 27, 2022
  48. Abhradeep ChakrabortyJun 27, 2022
  49. 3/6 pack-bitmap-write: learn pack.writeBitmapLookupTable and add testsAbhradeep Chakraborty, Jun 27, 2022
  50. Taylor BlauJun 27, 2022
  51. Taylor BlauJun 27, 2022
  52. Abhradeep ChakrabortyJun 27, 2022
  53. Abhradeep ChakrabortyJun 27, 2022
  54. Derrick StoleeJun 27, 2022
  55. Abhradeep ChakrabortyJun 27, 2022
  56. Taylor BlauJun 27, 2022
  57. Taylor BlauJun 27, 2022
  58. Taylor BlauJun 27, 2022
  59. Taylor BlauJun 27, 2022
  60. Abhradeep ChakrabortyJun 28, 2022
  61. Abhradeep ChakrabortyJun 28, 2022
  62. Abhradeep ChakrabortyJun 28, 2022
  63. Abhradeep ChakrabortyJun 28, 2022
  64. Taylor BlauJun 29, 2022
  65. Taylor BlauJun 29, 2022
  66. Taylor BlauJun 29, 2022
  67. Taylor BlauJun 29, 2022
  68. Taylor BlauJun 29, 2022
  69. Abhradeep ChakrabortyJun 30, 2022
  70. Abhradeep ChakrabortyJun 30, 2022
  71. 2/6 pack-bitmap-write.c: write lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 4, 2022
  72. 1/6 Documentation/technical: describe bitmap lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 4, 2022
  73. 0/6 [GSoC] bitmap: integrate a lookup table extension to the bitmap formatAbhradeep Chakraborty via GitGitGadget, Jul 4, 2022
  74. 3/6 pack-bitmap-write: learn pack.writeBitmapLookupTable and add testsAbhradeep Chakraborty via GitGitGadget, Jul 4, 2022
  75. 4/6 pack-bitmap: prepare to read lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 4, 2022
  76. 5/6 bitmap-lookup-table: add performance tests for lookup tableAbhradeep Chakraborty via GitGitGadget, Jul 4, 2022
  77. 6/6 p5310-pack-bitmaps.sh: remove pack.writeReverseIndexAbhradeep Chakraborty via GitGitGadget, Jul 4, 2022
  78. Abhradeep ChakrabortyJul 4, 2022
  79. Junio C HamanoJul 6, 2022
  80. Abhradeep ChakrabortyJul 7, 2022
  81. Kaartic SivaraamJul 7, 2022
  82. Abhradeep ChakrabortyJul 7, 2022
  83. Philip OakleyJul 8, 2022
  84. Abhradeep ChakrabortyJul 9, 2022
  85. Philip OakleyJul 10, 2022
  86. Taylor BlauJul 14, 2022
  87. Taylor BlauJul 14, 2022
  88. Taylor BlauJul 15, 2022
  89. Taylor BlauJul 15, 2022
  90. Taylor BlauJul 15, 2022
  91. Philip OakleyJul 15, 2022
  92. Abhradeep ChakrabortyJul 15, 2022
  93. Abhradeep ChakrabortyJul 15, 2022
  94. Abhradeep ChakrabortyJul 15, 2022
  95. Abhradeep ChakrabortyJul 15, 2022
  96. Taylor BlauJul 15, 2022
  97. Taylor BlauJul 15, 2022
  98. Abhradeep ChakrabortyJul 16, 2022
  99. Martin ÅgrenJul 18, 2022
  100. Martin ÅgrenJul 18, 2022
  101. Abhradeep ChakrabortyJul 18, 2022
  102. Martin ÅgrenJul 18, 2022
  103. 1/6 Documentation/technical: describe bitmap lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  104. 2/6 pack-bitmap-write.c: write lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  105. 0/6 [GSoC] bitmap: integrate a lookup table extension to the bitmap formatAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  106. 4/6 pack-bitmap: prepare to read lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  107. 5/6 p5310-pack-bitmaps.sh: enable `pack.writeReverseIndex`Abhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  108. 3/6 pack-bitmap-write: learn pack.writeBitmapLookupTable and add testsAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  109. 6/6 bitmap-lookup-table: add performance tests for lookup tableAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  110. 0/6 [GSoC] bitmap: integrate a lookup table extension to the bitmap formatAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  111. 1/6 Documentation/technical: describe bitmap lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  112. 2/6 pack-bitmap-write.c: write lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  113. 4/6 pack-bitmap: prepare to read lookup table extensionAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  114. 5/6 p5310-pack-bitmaps.sh: enable `pack.writeReverseIndex`Abhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  115. 6/6 bitmap-lookup-table: add performance tests for lookup tableAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  116. 3/6 pack-bitmap-write: learn pack.writeBitmapLookupTable and add testsAbhradeep Chakraborty via GitGitGadget, Jul 20, 2022
  117. Taylor BlauJul 26, 2022
  118. Taylor BlauJul 26, 2022
  119. Taylor BlauJul 26, 2022
  120. Taylor BlauJul 26, 2022
  121. Taylor BlauJul 26, 2022
  122. Ævar Arnfjörð BjarmasonJul 26, 2022
  123. Derrick StoleeJul 26, 2022
  124. Ævar Arnfjörð BjarmasonJul 26, 2022
  125. Abhradeep ChakrabortyJul 26, 2022
  126. Abhradeep ChakrabortyJul 26, 2022
  127. Abhradeep ChakrabortyJul 26, 2022
  128. Eric SunshineJul 26, 2022
  129. Johannes SchindelinJul 28, 2022
  130. Abhradeep ChakrabortyAug 2, 2022
  131. Johannes SchindelinAug 2, 2022
  132. Abhradeep ChakrabortyAug 2, 2022
  133. Johannes SchindelinAug 8, 2022
  134. Abhradeep ChakrabortyAug 8, 2022
  135. Johannes SchindelinAug 9, 2022
  136. Abhradeep ChakrabortyAug 9, 2022
  137. Abhradeep ChakrabortyAug 9, 2022
  138. Johannes SchindelinAug 10, 2022
  139. Johannes SchindelinAug 10, 2022
  140. Abhradeep ChakrabortyAug 10, 2022
  141. Derrick StoleeAug 10, 2022
  142. Abhradeep ChakrabortyAug 12, 2022
  143. Derrick StoleeAug 12, 2022
  144. Abhradeep ChakrabortyAug 13, 2022
  145. Abhradeep ChakrabortyAug 13, 2022
  146. 2/6 bitmap: move `get commit positions` code to `bitmap_writer_finish`Abhradeep Chakraborty via GitGitGadget, Aug 14, 2022
  147. 0/6 [GSoC] bitmap: integrate a lookup table extension to the bitmap formatAbhradeep Chakraborty via GitGitGadget, Aug 14, 2022
  148. 1/6 Documentation/technical: describe bitmap lookup table extensionAbhradeep Chakraborty via GitGitGadget, Aug 14, 2022
  149. 3/6 pack-bitmap-write.c: write lookup table extensionAbhradeep Chakraborty via GitGitGadget, Aug 14, 2022
  150. 5/6 pack-bitmap: prepare to read lookup table extensionAbhradeep Chakraborty via GitGitGadget, Aug 14, 2022
  151. 4/6 pack-bitmap-write: learn pack.writeBitmapLookupTable and add testsAbhradeep Chakraborty via GitGitGadget, Aug 14, 2022
  152. 6/6 bitmap-lookup-table: add performance tests for lookup tableAbhradeep Chakraborty via GitGitGadget, Aug 14, 2022
  153. Taylor BlauAug 16, 2022
  154. Taylor BlauAug 16, 2022
  155. Abhradeep ChakrabortyAug 17, 2022
  156. Taylor BlauAug 17, 2022
  157. Junio C HamanoAug 19, 2022
  158. Taylor BlauAug 19, 2022
  159. Johannes SchindelinAug 22, 2022
  160. Taylor BlauAug 22, 2022
  161. Taylor BlauAug 25, 2022
  162. Junio C HamanoAug 26, 2022

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