Mercurial > hg
view tests/test-flags.t @ 27430:e240e914d226 stable
revlog: seek to end of file before writing (issue4943)
Revlogs were recently refactored to open file handles in "a+" and use a
persistent file handle for reading and writing. This drastically
reduced the number of file handles being opened.
Unfortunately, it appears that some versions of Solaris lose the file
offset when performing a write after the handle has been seeked.
The simplest workaround is to seek to EOF on files opened in a+ mode
before writing to them, which is what this patch does.
Ideally, this code would exist in the vfs layer. However, this would
require creating a proxy class for file objects in order to provide a
custom implementation of write(). This would add overhead. Since
revlogs are the only files we open in a+ mode, the one-off workaround
in revlog.py should be sufficient.
This patch appears to have little to no impact on performance on my
Linux machine.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Thu, 17 Dec 2015 17:16:02 -0800 |
parents | 7a9cbb315d84 |
children | eb586ed5d8ce |
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#require execbit $ umask 027 $ hg init test1 $ cd test1 $ touch a b $ hg add a b $ hg ci -m "added a b" $ cd .. $ hg clone test1 test3 updating to branch default 2 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg init test2 $ cd test2 $ hg pull ../test1 pulling from ../test1 requesting all changes adding changesets adding manifests adding file changes added 1 changesets with 2 changes to 2 files (run 'hg update' to get a working copy) $ hg co 2 files updated, 0 files merged, 0 files removed, 0 files unresolved $ chmod +x a $ hg ci -m "chmod +x a" the changelog should mention file a: $ hg tip --template '{files}\n' a $ cd ../test1 $ echo 123 >>a $ hg ci -m "a updated" $ hg pull ../test2 pulling from ../test2 searching for changes adding changesets adding manifests adding file changes added 1 changesets with 0 changes to 0 files (+1 heads) (run 'hg heads' to see heads, 'hg merge' to merge) $ hg heads changeset: 2:7f4313b42a34 tag: tip parent: 0:22a449e20da5 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: chmod +x a changeset: 1:c6ecefc45368 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: a updated $ hg history changeset: 2:7f4313b42a34 tag: tip parent: 0:22a449e20da5 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: chmod +x a changeset: 1:c6ecefc45368 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: a updated changeset: 0:22a449e20da5 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: added a b $ hg -v merge resolving manifests 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ cat a 123 $ [ -x a ] $ cd ../test3 $ echo 123 >>b $ hg ci -m "b updated" $ hg pull ../test2 pulling from ../test2 searching for changes adding changesets adding manifests adding file changes added 1 changesets with 0 changes to 0 files (+1 heads) (run 'hg heads' to see heads, 'hg merge' to merge) $ hg heads changeset: 2:7f4313b42a34 tag: tip parent: 0:22a449e20da5 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: chmod +x a changeset: 1:dc57ead75f79 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: b updated $ hg history changeset: 2:7f4313b42a34 tag: tip parent: 0:22a449e20da5 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: chmod +x a changeset: 1:dc57ead75f79 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: b updated changeset: 0:22a449e20da5 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: added a b $ hg -v merge resolving manifests 1 files updated, 0 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ ls -l ../test[123]/a > foo $ cut -b 1-10 < foo -rwxr-x--- -rwxr-x--- -rwxr-x--- $ hg debugindex a rev offset length ..... linkrev nodeid p1 p2 (re) 0 0 0 ..... 0 b80de5d13875 000000000000 000000000000 (re) $ hg debugindex -R ../test2 a rev offset length ..... linkrev nodeid p1 p2 (re) 0 0 0 ..... 0 b80de5d13875 000000000000 000000000000 (re) $ hg debugindex -R ../test1 a rev offset length ..... linkrev nodeid p1 p2 (re) 0 0 0 ..... 0 b80de5d13875 000000000000 000000000000 (re) 1 0 5 ..... 1 7fe919cc0336 b80de5d13875 000000000000 (re) $ cd ..