Mercurial > hg
view tests/test-up-local-change.t @ 30212:260af19891f2
changegroup: increase write buffer size to 128k
By default, Python defers to the operating system for choosing the
default buffer size on opened files. On my Linux machine, the default
is 4k, which is really small for 2016.
This patch bumps the write buffer size when writing
changegroups/bundles to 128k. This matches the 128k read buffer
we already use on revlogs.
It's worth noting that this only impacts when writing to an explicit
file (such as during `hg bundle`). Buffers when writing to bundle
files via the repo vfs or to a temporary file are not impacted.
When producing a none-v2 bundle file of the mozilla-unified repository,
this change caused the number of write() system calls to drop from
952,449 to 29,788. After this change, the most frequent system
calls are fstat(), read(), lseek(), and open(). There were
2,523,672 system calls after this patch (so a net decrease of
~950k is statistically significant).
This change shows no performance change on my system. But I have a
high-end system with a fast SSD. It is quite possible this change
will have a significant impact on network file systems, where
extra network round trips due to excessive I/O system calls could
introduce significant latency.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sun, 16 Oct 2016 13:35:23 -0700 |
parents | a2804ddcf9ae |
children | 69ffbbe73dd0 |
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$ HGMERGE=true; export HGMERGE $ hg init r1 $ cd r1 $ echo a > a $ hg addremove adding a $ hg commit -m "1" $ hg clone . ../r2 updating to branch default 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cd ../r2 $ hg up 0 files updated, 0 files merged, 0 files removed, 0 files unresolved $ echo abc > a $ hg diff --nodates diff -r c19d34741b0a a --- a/a +++ b/a @@ -1,1 +1,1 @@ -a +abc $ cd ../r1 $ echo b > b $ echo a2 > a $ hg addremove adding b $ hg commit -m "2" $ cd ../r2 $ hg -q pull ../r1 $ hg status M a $ hg parents changeset: 0:c19d34741b0a user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 1 $ hg --debug up searching for copies back to rev 1 unmatched files in other: b resolving manifests branchmerge: False, force: False, partial: False ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb preserving a for resolve of a b: remote created -> g getting b a: versions differ -> m (premerge) picked tool 'true' for a (binary False symlink False changedelete False) merging a my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a a: versions differ -> m (merge) picked tool 'true' for a (binary False symlink False changedelete False) my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a launching merge tool: true *$TESTTMP/r2/a* * * (glob) merge tool returned: 0 1 files updated, 1 files merged, 0 files removed, 0 files unresolved $ hg parents changeset: 1:1e71731e6fbb tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 2 $ hg --debug up 0 starting 4 threads for background file closing (?) searching for copies back to rev 0 unmatched files in local (from topological common ancestor): b resolving manifests branchmerge: False, force: False, partial: False ancestor: 1e71731e6fbb, local: 1e71731e6fbb+, remote: c19d34741b0a preserving a for resolve of a b: other deleted -> r removing b starting 4 threads for background file closing (?) a: versions differ -> m (premerge) picked tool 'true' for a (binary False symlink False changedelete False) merging a my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb a: versions differ -> m (merge) picked tool 'true' for a (binary False symlink False changedelete False) my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb launching merge tool: true *$TESTTMP/r2/a* * * (glob) merge tool returned: 0 0 files updated, 1 files merged, 1 files removed, 0 files unresolved $ hg parents changeset: 0:c19d34741b0a user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 1 $ hg --debug up searching for copies back to rev 1 unmatched files in other: b resolving manifests branchmerge: False, force: False, partial: False ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb preserving a for resolve of a b: remote created -> g getting b a: versions differ -> m (premerge) picked tool 'true' for a (binary False symlink False changedelete False) merging a my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a a: versions differ -> m (merge) picked tool 'true' for a (binary False symlink False changedelete False) my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a launching merge tool: true *$TESTTMP/r2/a* * * (glob) merge tool returned: 0 1 files updated, 1 files merged, 0 files removed, 0 files unresolved $ hg parents changeset: 1:1e71731e6fbb tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 2 $ hg -v history changeset: 1:1e71731e6fbb tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 files: a b description: 2 changeset: 0:c19d34741b0a user: test date: Thu Jan 01 00:00:00 1970 +0000 files: a description: 1 $ hg diff --nodates diff -r 1e71731e6fbb a --- a/a +++ b/a @@ -1,1 +1,1 @@ -a2 +abc create a second head $ cd ../r1 $ hg up 0 1 files updated, 0 files merged, 1 files removed, 0 files unresolved $ echo b2 > b $ echo a3 > a $ hg addremove adding b $ hg commit -m "3" created new head $ cd ../r2 $ hg -q pull ../r1 $ hg status M a $ hg parents changeset: 1:1e71731e6fbb user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 2 $ hg --debug up 0 files updated, 0 files merged, 0 files removed, 0 files unresolved 1 other heads for branch "default" test conflicting untracked files $ hg up -qC 0 $ echo untracked > b $ hg st ? b $ hg up 1 b: untracked file differs abort: untracked files in working directory differ from files in requested revision [255] $ rm b test conflicting untracked ignored file $ hg up -qC 0 $ echo ignored > .hgignore $ hg add .hgignore $ hg ci -m 'add .hgignore' created new head $ echo ignored > ignored $ hg add ignored $ hg ci -m 'add ignored file' $ hg up -q 'desc("add .hgignore")' $ echo untracked > ignored $ hg st $ hg up 'desc("add ignored file")' ignored: untracked file differs abort: untracked files in working directory differ from files in requested revision [255] test a local add $ cd .. $ hg init a $ hg init b $ echo a > a/a $ echo a > b/a $ hg --cwd a commit -A -m a adding a $ cd b $ hg add a $ hg pull -u ../a pulling from ../a requesting all changes adding changesets adding manifests adding file changes added 1 changesets with 1 changes to 1 files 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg st test updating backwards through a rename $ hg mv a b $ hg ci -m b $ echo b > b $ hg up -q 0 $ hg st M a $ hg diff --nodates diff -r cb9a9f314b8b a --- a/a +++ b/a @@ -1,1 +1,1 @@ -a +b $ cd ..