Mercurial > hg
view tests/test-merge-local.t @ 44363:f7459da77f23
nodemap: introduce an option to use mmap to read the nodemap mapping
The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.
This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).
Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:
Before:
* do not use the persistent nodemap
* use the CPython implementation of the index for nodemap
* use mmapping of the changelog index
After:
* use the MixedIndex Rust code, with the NodeTree object for nodemap access
(still in review)
* use the persistent nodemap data from disk
* access the persistent nodemap data through mmap
* use mmapping of the changelog index
The persistent nodemap greatly speed up most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.
Here are some numbers (in seconds) for the reference copy of mozilla-try:
Revset Before After abs-change speedup
-10000: 0.004622 0.005532 0.000910 × 0.83
-10: 0.000050 0.000132 0.000082 × 0.37
tip 0.000052 0.000085 0.000033 × 0.61
0 + (-10000:) 0.028222 0.005337 -0.022885 × 5.29
0 0.023521 0.000084 -0.023437 × 280.01
(-10000:) + 0 0.235539 0.005308 -0.230231 × 44.37
(-10:) + :9 0.232883 0.000180 -0.232703 ×1293.79
(-10000:) + (:99) 0.238735 0.005358 -0.233377 × 44.55
:99 + (-10000:) 0.317942 0.005593 -0.312349 × 56.84
:9 + (-10:) 0.313372 0.000179 -0.313193 ×1750.68
:9 0.316450 0.000143 -0.316307 ×2212.93
On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.
Here are some numbers (in seconds) for the reference copy of mercurial:
Revset Before After abs-change speedup
-10: 0.000065 0.000097 0.000032 × 0.67
tip 0.000063 0.000078 0.000015 × 0.80
0 0.000561 0.000079 -0.000482 × 7.10
-10000: 0.004609 0.003648 -0.000961 × 1.26
0 + (-10000:) 0.005023 0.003715 -0.001307 × 1.35
(-10:) + :9 0.002187 0.000108 -0.002079 ×20.25
(-10000:) + 0 0.006252 0.003716 -0.002536 × 1.68
(-10000:) + (:99) 0.006367 0.003707 -0.002660 × 1.71
:9 + (-10:) 0.003846 0.000110 -0.003736 ×34.96
:9 0.003854 0.000099 -0.003755 ×38.92
:99 + (-10000:) 0.007644 0.003778 -0.003866 × 2.02
Differential Revision: https://phab.mercurial-scm.org/D7894
| author | Pierre-Yves David <pierre-yves.david@octobus.net> |
|---|---|
| date | Tue, 11 Feb 2020 11:18:52 +0100 |
| parents | 9e4f82bc2b0b |
| children | 55c6ebd11cb9 |
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$ hg init Revision 0: $ echo "unchanged" > unchanged $ echo "remove me" > remove $ echo "copy me" > copy $ echo "move me" > move $ for i in 1 2 3 4 5 6 7 8 9; do > echo "merge ok $i" >> zzz1_merge_ok > done $ echo "merge bad" > zzz2_merge_bad $ hg ci -Am "revision 0" adding copy adding move adding remove adding unchanged adding zzz1_merge_ok adding zzz2_merge_bad Revision 1: $ hg rm remove $ hg mv move moved $ hg cp copy copied $ echo "added" > added $ hg add added $ echo "new first line" > zzz1_merge_ok $ hg cat zzz1_merge_ok >> zzz1_merge_ok $ echo "new last line" >> zzz2_merge_bad $ hg ci -m "revision 1" Local changes to revision 0: $ hg co 0 4 files updated, 0 files merged, 3 files removed, 0 files unresolved $ echo "new last line" >> zzz1_merge_ok $ echo "another last line" >> zzz2_merge_bad $ hg diff --nodates | grep "^[+-][^<>]" --- a/zzz1_merge_ok +++ b/zzz1_merge_ok +new last line --- a/zzz2_merge_bad +++ b/zzz2_merge_bad +another last line $ hg st M zzz1_merge_ok M zzz2_merge_bad Local merge with bad merge tool: $ HGMERGE=false hg co merging zzz1_merge_ok merging zzz2_merge_bad merging zzz2_merge_bad failed! 3 files updated, 1 files merged, 2 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges [1] $ hg resolve -m (no more unresolved files) $ hg co 0 merging zzz1_merge_ok merging zzz2_merge_bad warning: conflicts while merging zzz2_merge_bad! (edit, then use 'hg resolve --mark') 2 files updated, 1 files merged, 3 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges [1] $ hg diff --nodates | grep "^[+-][^<>]" --- a/zzz1_merge_ok +++ b/zzz1_merge_ok +new last line --- a/zzz2_merge_bad +++ b/zzz2_merge_bad +another last line +======= $ hg st M zzz1_merge_ok M zzz2_merge_bad ? zzz2_merge_bad.orig Local merge with conflicts: $ hg resolve -m (no more unresolved files) $ hg co merging zzz1_merge_ok merging zzz2_merge_bad warning: conflicts while merging zzz2_merge_bad! (edit, then use 'hg resolve --mark') 3 files updated, 1 files merged, 2 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges [1] $ hg resolve -m (no more unresolved files) $ hg co 0 --config 'ui.origbackuppath=.hg/origbackups' merging zzz1_merge_ok merging zzz2_merge_bad warning: conflicts while merging zzz2_merge_bad! (edit, then use 'hg resolve --mark') 2 files updated, 1 files merged, 3 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges [1] Are orig files from the last commit where we want them? $ ls .hg/origbackups zzz2_merge_bad $ hg diff --nodates | grep "^[+-][^<>]" --- a/zzz1_merge_ok +++ b/zzz1_merge_ok +new last line --- a/zzz2_merge_bad +++ b/zzz2_merge_bad +another last line +======= +======= +new last line +======= $ hg st M zzz1_merge_ok M zzz2_merge_bad ? zzz2_merge_bad.orig Local merge without conflicts: $ hg revert zzz2_merge_bad $ hg resolve -m (no more unresolved files) $ hg co merging zzz1_merge_ok 4 files updated, 1 files merged, 2 files removed, 0 files unresolved $ hg diff --nodates | grep "^[+-][^<>]" --- a/zzz1_merge_ok +++ b/zzz1_merge_ok +new last line $ hg st M zzz1_merge_ok ? zzz2_merge_bad.orig