Mercurial > hg
view tests/test-generaldelta.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 | 953839de96ab |
children | 318a24b52eeb |
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Check whether size of generaldelta revlog is not bigger than its regular equivalent. Test would fail if generaldelta was naive implementation of parentdelta: third manifest revision would be fully inserted due to big distance from its paren revision (zero). $ hg init repo --config format.generaldelta=no --config format.usegeneraldelta=no $ cd repo $ echo foo > foo $ echo bar > bar $ echo baz > baz $ hg commit -q -Am boo $ hg clone --pull . ../gdrepo -q --config format.generaldelta=yes $ for r in 1 2 3; do > echo $r > foo > hg commit -q -m $r > hg up -q -r 0 > hg pull . -q -r $r -R ../gdrepo > done $ cd .. >>> from __future__ import print_function >>> import os >>> regsize = os.stat("repo/.hg/store/00manifest.i").st_size >>> gdsize = os.stat("gdrepo/.hg/store/00manifest.i").st_size >>> if regsize < gdsize: ... print('generaldata increased size of manifest') Verify rev reordering doesnt create invalid bundles (issue4462) This requires a commit tree that when pulled will reorder manifest revs such that the second manifest to create a file rev will be ordered before the first manifest to create that file rev. We also need to do a partial pull to ensure reordering happens. At the end we verify the linkrev points at the earliest commit. $ hg init server --config format.generaldelta=True $ cd server $ touch a $ hg commit -Aqm a $ echo x > x $ echo y > y $ hg commit -Aqm xy $ hg up -q '.^' $ echo x > x $ echo z > z $ hg commit -Aqm xz $ hg up -q 1 $ echo b > b $ hg commit -Aqm b $ hg merge -q 2 $ hg commit -Aqm merge $ echo c > c $ hg commit -Aqm c $ hg log -G -T '{rev} {shortest(node)} {desc}' @ 5 ebb8 c | o 4 baf7 merge |\ | o 3 a129 b | | o | 2 958c xz | | | o 1 f00c xy |/ o 0 3903 a $ cd .. $ hg init client --config format.generaldelta=false --config format.usegeneraldelta=false $ cd client $ hg pull -q ../server -r 4 $ hg debugindex x rev offset length base linkrev nodeid p1 p2 0 0 3 0 1 1406e7411862 000000000000 000000000000 $ cd .. Test "usegeneraldelta" config (repo are general delta, but incoming bundle are not re-deltified) delta coming from the server base delta server are not recompressed. (also include the aggressive version for comparison) $ hg clone repo --pull --config format.usegeneraldelta=1 usegd requesting all changes adding changesets adding manifests adding file changes added 4 changesets with 6 changes to 3 files (+2 heads) updating to branch default 3 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg clone repo --pull --config format.generaldelta=1 full requesting all changes adding changesets adding manifests adding file changes added 4 changesets with 6 changes to 3 files (+2 heads) updating to branch default 3 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg -R repo debugindex -m rev offset length base linkrev nodeid p1 p2 0 0 104 0 0 cef96823c800 000000000000 000000000000 1 104 57 0 1 58ab9a8d541d cef96823c800 000000000000 2 161 57 0 2 134fdc6fd680 cef96823c800 000000000000 3 218 104 3 3 723508934dad cef96823c800 000000000000 $ hg -R usegd debugindex -m rev offset length delta linkrev nodeid p1 p2 0 0 104 -1 0 cef96823c800 000000000000 000000000000 1 104 57 0 1 58ab9a8d541d cef96823c800 000000000000 2 161 57 1 2 134fdc6fd680 cef96823c800 000000000000 3 218 57 0 3 723508934dad cef96823c800 000000000000 $ hg -R full debugindex -m rev offset length delta linkrev nodeid p1 p2 0 0 104 -1 0 cef96823c800 000000000000 000000000000 1 104 57 0 1 58ab9a8d541d cef96823c800 000000000000 2 161 57 0 2 134fdc6fd680 cef96823c800 000000000000 3 218 57 0 3 723508934dad cef96823c800 000000000000 Test format.aggressivemergedeltas $ hg init --config format.generaldelta=1 aggressive $ cd aggressive $ cat << EOF >> .hg/hgrc > [format] > generaldelta = 1 > EOF $ touch a b c d e $ hg commit -Aqm side1 $ hg up -q null $ touch x y $ hg commit -Aqm side2 - Verify non-aggressive merge uses p1 (commit 1) as delta parent $ hg merge -q 0 $ hg commit -q -m merge $ hg debugindex -m rev offset length delta linkrev nodeid p1 p2 0 0 59 -1 0 8dde941edb6e 000000000000 000000000000 1 59 61 0 1 315c023f341d 000000000000 000000000000 2 120 65 1 2 2ab389a983eb 315c023f341d 8dde941edb6e $ hg strip -q -r . --config extensions.strip= - Verify aggressive merge uses p2 (commit 0) as delta parent $ hg up -q -C 1 $ hg merge -q 0 $ hg commit -q -m merge --config format.aggressivemergedeltas=True $ hg debugindex -m rev offset length delta linkrev nodeid p1 p2 0 0 59 -1 0 8dde941edb6e 000000000000 000000000000 1 59 61 0 1 315c023f341d 000000000000 000000000000 2 120 62 0 2 2ab389a983eb 315c023f341d 8dde941edb6e Test that strip bundle use bundle2 $ hg --config extensions.strip= strip . 0 files updated, 0 files merged, 5 files removed, 0 files unresolved saved backup bundle to $TESTTMP/aggressive/.hg/strip-backup/1c5d4dc9a8b8-6c68e60c-backup.hg (glob) $ hg debugbundle .hg/strip-backup/* Stream params: sortdict([('Compression', 'BZ')]) changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])" 1c5d4dc9a8b8d6e1750966d343e94db665e7a1e9 $ cd ..