git-commit-vandalism/t/perf/p2000-sparse-operations.sh

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t/perf: add performance test for sparse operations Create a test script that takes the default performance test (the Git codebase) and multiplies it by 256 using four layers of duplicated trees of width four. This results in nearly one million blob entries in the index. Then, we can clone this repository with sparse-checkout patterns that demonstrate four copies of the initial repository. Each clone will use a different index format or mode so peformance can be tested across the different options. Note that the initial repo is stripped of submodules before doing the copies. This preserves the expected data shape of the sparse index, because directories containing submodules are not collapsed to a sparse directory entry. Run a few Git commands on these clones, especially those that use the index (status, add, commit). Here are the results on my Linux machine: Test -------------------------------------------------------------- 2000.2: git status (full-index-v3) 0.37(0.30+0.09) 2000.3: git status (full-index-v4) 0.39(0.32+0.10) 2000.4: git add -A (full-index-v3) 1.42(1.06+0.20) 2000.5: git add -A (full-index-v4) 1.26(0.98+0.16) 2000.6: git add . (full-index-v3) 1.40(1.04+0.18) 2000.7: git add . (full-index-v4) 1.26(0.98+0.17) 2000.8: git commit -a -m A (full-index-v3) 1.42(1.11+0.16) 2000.9: git commit -a -m A (full-index-v4) 1.33(1.08+0.16) It is perhaps noteworthy that there is an improvement when using index version 4. This is because the v3 index uses 108 MiB while the v4 index uses 80 MiB. Since the repeated portions of the directories are very short (f3/f1/f2, for example) this ratio is less pronounced than in similarly-sized real repositories. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-30 15:10:45 +02:00
#!/bin/sh
test_description="test performance of Git operations using the index"
. ./perf-lib.sh
test_perf_default_repo
SPARSE_CONE=f2/f4/f1
test_expect_success 'setup repo and indexes' '
git reset --hard HEAD &&
# Remove submodules from the example repo, because our
# duplication of the entire repo creates an unlikely data shape.
if git config --file .gitmodules --get-regexp "submodule.*.path" >modules
then
git rm $(awk "{print \$2}" modules) &&
git commit -m "remove submodules" || return 1
fi &&
echo bogus >a &&
cp a b &&
git add a b &&
git commit -m "level 0" &&
BLOB=$(git rev-parse HEAD:a) &&
OLD_COMMIT=$(git rev-parse HEAD) &&
OLD_TREE=$(git rev-parse HEAD^{tree}) &&
for i in $(test_seq 1 4)
do
cat >in <<-EOF &&
100755 blob $BLOB a
040000 tree $OLD_TREE f1
040000 tree $OLD_TREE f2
040000 tree $OLD_TREE f3
040000 tree $OLD_TREE f4
EOF
NEW_TREE=$(git mktree <in) &&
NEW_COMMIT=$(git commit-tree $NEW_TREE -p $OLD_COMMIT -m "level $i") &&
OLD_TREE=$NEW_TREE &&
OLD_COMMIT=$NEW_COMMIT || return 1
done &&
git sparse-checkout init --cone &&
git branch -f wide $OLD_COMMIT &&
git -c core.sparseCheckoutCone=true clone --branch=wide --sparse . full-index-v3 &&
(
cd full-index-v3 &&
git sparse-checkout init --cone &&
git sparse-checkout set $SPARSE_CONE &&
git config index.version 3 &&
git update-index --index-version=3
) &&
git -c core.sparseCheckoutCone=true clone --branch=wide --sparse . full-index-v4 &&
(
cd full-index-v4 &&
git sparse-checkout init --cone &&
git sparse-checkout set $SPARSE_CONE &&
git config index.version 4 &&
git update-index --index-version=4
p2000: add sparse-index repos p2000-sparse-operations.sh compares different Git commands in repositories with many files at HEAD but using sparse-checkout to focus on a small portion of those files. Add extra copies of the repository that use the sparse-index format so we can track how that affects the performance of different commands. At this point in time, the sparse-index is 100% overhead from the CPU front, and this is measurable in these tests: Test --------------------------------------------------------------- 2000.2: git status (full-index-v3) 0.59(0.51+0.12) 2000.3: git status (full-index-v4) 0.59(0.52+0.11) 2000.4: git status (sparse-index-v3) 1.40(1.32+0.12) 2000.5: git status (sparse-index-v4) 1.41(1.36+0.08) 2000.6: git add -A (full-index-v3) 2.32(1.97+0.19) 2000.7: git add -A (full-index-v4) 2.17(1.92+0.14) 2000.8: git add -A (sparse-index-v3) 2.31(2.21+0.15) 2000.9: git add -A (sparse-index-v4) 2.30(2.20+0.13) 2000.10: git add . (full-index-v3) 2.39(2.02+0.20) 2000.11: git add . (full-index-v4) 2.20(1.94+0.16) 2000.12: git add . (sparse-index-v3) 2.36(2.27+0.12) 2000.13: git add . (sparse-index-v4) 2.33(2.21+0.16) 2000.14: git commit -a -m A (full-index-v3) 2.47(2.12+0.20) 2000.15: git commit -a -m A (full-index-v4) 2.26(2.00+0.17) 2000.16: git commit -a -m A (sparse-index-v3) 3.01(2.92+0.16) 2000.17: git commit -a -m A (sparse-index-v4) 3.01(2.94+0.15) Note that there is very little difference between the v3 and v4 index formats when the sparse-index is enabled. This is primarily due to the fact that the relative file sizes are the same, and the command time is mostly taken up by parsing tree objects to expand the sparse index into a full one. With the current file layout, the index file sizes are given by this table: | full index | sparse index | +-------------+--------------+ v3 | 108 MiB | 1.6 MiB | v4 | 80 MiB | 1.2 MiB | Future updates will improve the performance of Git commands when the index is sparse. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-30 15:11:04 +02:00
) &&
git -c core.sparseCheckoutCone=true clone --branch=wide --sparse . sparse-index-v3 &&
(
cd sparse-index-v3 &&
git sparse-checkout init --cone --sparse-index &&
git sparse-checkout set $SPARSE_CONE &&
git config index.version 3 &&
git update-index --index-version=3
) &&
git -c core.sparseCheckoutCone=true clone --branch=wide --sparse . sparse-index-v4 &&
(
cd sparse-index-v4 &&
git sparse-checkout init --cone --sparse-index &&
git sparse-checkout set $SPARSE_CONE &&
git config index.version 4 &&
git update-index --index-version=4
t/perf: add performance test for sparse operations Create a test script that takes the default performance test (the Git codebase) and multiplies it by 256 using four layers of duplicated trees of width four. This results in nearly one million blob entries in the index. Then, we can clone this repository with sparse-checkout patterns that demonstrate four copies of the initial repository. Each clone will use a different index format or mode so peformance can be tested across the different options. Note that the initial repo is stripped of submodules before doing the copies. This preserves the expected data shape of the sparse index, because directories containing submodules are not collapsed to a sparse directory entry. Run a few Git commands on these clones, especially those that use the index (status, add, commit). Here are the results on my Linux machine: Test -------------------------------------------------------------- 2000.2: git status (full-index-v3) 0.37(0.30+0.09) 2000.3: git status (full-index-v4) 0.39(0.32+0.10) 2000.4: git add -A (full-index-v3) 1.42(1.06+0.20) 2000.5: git add -A (full-index-v4) 1.26(0.98+0.16) 2000.6: git add . (full-index-v3) 1.40(1.04+0.18) 2000.7: git add . (full-index-v4) 1.26(0.98+0.17) 2000.8: git commit -a -m A (full-index-v3) 1.42(1.11+0.16) 2000.9: git commit -a -m A (full-index-v4) 1.33(1.08+0.16) It is perhaps noteworthy that there is an improvement when using index version 4. This is because the v3 index uses 108 MiB while the v4 index uses 80 MiB. Since the repeated portions of the directories are very short (f3/f1/f2, for example) this ratio is less pronounced than in similarly-sized real repositories. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-30 15:10:45 +02:00
)
'
test_perf_on_all () {
command="$@"
p2000: add sparse-index repos p2000-sparse-operations.sh compares different Git commands in repositories with many files at HEAD but using sparse-checkout to focus on a small portion of those files. Add extra copies of the repository that use the sparse-index format so we can track how that affects the performance of different commands. At this point in time, the sparse-index is 100% overhead from the CPU front, and this is measurable in these tests: Test --------------------------------------------------------------- 2000.2: git status (full-index-v3) 0.59(0.51+0.12) 2000.3: git status (full-index-v4) 0.59(0.52+0.11) 2000.4: git status (sparse-index-v3) 1.40(1.32+0.12) 2000.5: git status (sparse-index-v4) 1.41(1.36+0.08) 2000.6: git add -A (full-index-v3) 2.32(1.97+0.19) 2000.7: git add -A (full-index-v4) 2.17(1.92+0.14) 2000.8: git add -A (sparse-index-v3) 2.31(2.21+0.15) 2000.9: git add -A (sparse-index-v4) 2.30(2.20+0.13) 2000.10: git add . (full-index-v3) 2.39(2.02+0.20) 2000.11: git add . (full-index-v4) 2.20(1.94+0.16) 2000.12: git add . (sparse-index-v3) 2.36(2.27+0.12) 2000.13: git add . (sparse-index-v4) 2.33(2.21+0.16) 2000.14: git commit -a -m A (full-index-v3) 2.47(2.12+0.20) 2000.15: git commit -a -m A (full-index-v4) 2.26(2.00+0.17) 2000.16: git commit -a -m A (sparse-index-v3) 3.01(2.92+0.16) 2000.17: git commit -a -m A (sparse-index-v4) 3.01(2.94+0.15) Note that there is very little difference between the v3 and v4 index formats when the sparse-index is enabled. This is primarily due to the fact that the relative file sizes are the same, and the command time is mostly taken up by parsing tree objects to expand the sparse index into a full one. With the current file layout, the index file sizes are given by this table: | full index | sparse index | +-------------+--------------+ v3 | 108 MiB | 1.6 MiB | v4 | 80 MiB | 1.2 MiB | Future updates will improve the performance of Git commands when the index is sparse. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-30 15:11:04 +02:00
for repo in full-index-v3 full-index-v4 \
sparse-index-v3 sparse-index-v4
t/perf: add performance test for sparse operations Create a test script that takes the default performance test (the Git codebase) and multiplies it by 256 using four layers of duplicated trees of width four. This results in nearly one million blob entries in the index. Then, we can clone this repository with sparse-checkout patterns that demonstrate four copies of the initial repository. Each clone will use a different index format or mode so peformance can be tested across the different options. Note that the initial repo is stripped of submodules before doing the copies. This preserves the expected data shape of the sparse index, because directories containing submodules are not collapsed to a sparse directory entry. Run a few Git commands on these clones, especially those that use the index (status, add, commit). Here are the results on my Linux machine: Test -------------------------------------------------------------- 2000.2: git status (full-index-v3) 0.37(0.30+0.09) 2000.3: git status (full-index-v4) 0.39(0.32+0.10) 2000.4: git add -A (full-index-v3) 1.42(1.06+0.20) 2000.5: git add -A (full-index-v4) 1.26(0.98+0.16) 2000.6: git add . (full-index-v3) 1.40(1.04+0.18) 2000.7: git add . (full-index-v4) 1.26(0.98+0.17) 2000.8: git commit -a -m A (full-index-v3) 1.42(1.11+0.16) 2000.9: git commit -a -m A (full-index-v4) 1.33(1.08+0.16) It is perhaps noteworthy that there is an improvement when using index version 4. This is because the v3 index uses 108 MiB while the v4 index uses 80 MiB. Since the repeated portions of the directories are very short (f3/f1/f2, for example) this ratio is less pronounced than in similarly-sized real repositories. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-30 15:10:45 +02:00
do
test_perf "$command ($repo)" "
(
cd $repo &&
echo >>$SPARSE_CONE/a &&
$command
)
"
done
}
test_perf_on_all git status
test_perf_on_all git add -A
test_perf_on_all git add .
test_perf_on_all git commit -a -m A
test_done