Mercurial > hg
view tests/test-children.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 | 3eb9045396b0 |
children | 7c8524efd847 |
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test children command $ cat <<EOF >> $HGRCPATH > [extensions] > children = > EOF init $ hg init t $ cd t no working directory $ hg children setup $ echo 0 > file0 $ hg ci -qAm 0 -d '0 0' $ echo 1 > file1 $ hg ci -qAm 1 -d '1 0' $ echo 2 >> file0 $ hg ci -qAm 2 -d '2 0' $ hg co null 0 files updated, 0 files merged, 2 files removed, 0 files unresolved $ echo 3 > file3 $ hg ci -qAm 3 -d '3 0' hg children at revision 3 (tip) $ hg children $ hg co null 0 files updated, 0 files merged, 1 files removed, 0 files unresolved hg children at nullrev (should be 0 and 3) $ hg children changeset: 0:4df8521a7374 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 0 changeset: 3:e2962852269d tag: tip parent: -1:000000000000 user: test date: Thu Jan 01 00:00:03 1970 +0000 summary: 3 $ hg co 1 2 files updated, 0 files merged, 0 files removed, 0 files unresolved hg children at revision 1 (should be 2) $ hg children changeset: 2:8f5eea5023c2 user: test date: Thu Jan 01 00:00:02 1970 +0000 summary: 2 $ hg co 2 1 files updated, 0 files merged, 0 files removed, 0 files unresolved hg children at revision 2 (other head) $ hg children $ for i in null 0 1 2 3; do > echo "hg children -r $i" > hg children -r $i > done hg children -r null changeset: 0:4df8521a7374 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 0 changeset: 3:e2962852269d tag: tip parent: -1:000000000000 user: test date: Thu Jan 01 00:00:03 1970 +0000 summary: 3 hg children -r 0 changeset: 1:708c093edef0 user: test date: Thu Jan 01 00:00:01 1970 +0000 summary: 1 hg children -r 1 changeset: 2:8f5eea5023c2 user: test date: Thu Jan 01 00:00:02 1970 +0000 summary: 2 hg children -r 2 hg children -r 3 hg children -r 0 file0 (should be 2) $ hg children -r 0 file0 changeset: 2:8f5eea5023c2 user: test date: Thu Jan 01 00:00:02 1970 +0000 summary: 2 hg children -r 1 file0 (should be 2) $ hg children -r 1 file0 changeset: 2:8f5eea5023c2 user: test date: Thu Jan 01 00:00:02 1970 +0000 summary: 2 $ hg co 0 1 files updated, 0 files merged, 1 files removed, 0 files unresolved hg children file0 at revision 0 (should be 2) $ hg children file0 changeset: 2:8f5eea5023c2 user: test date: Thu Jan 01 00:00:02 1970 +0000 summary: 2 should be compatible with templater (don't pass fctx to displayer) $ hg children file0 -Tdefault changeset: 2:8f5eea5023c2 user: test date: Thu Jan 01 00:00:02 1970 +0000 summary: 2 $ cd ..