Mercurial > hg
view tests/test-mq-symlinks.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 | 4d2b9b304ad0 |
children | c2380b448265 |
line wrap: on
line source
#require symlink $ echo "[extensions]" >> $HGRCPATH $ echo "mq=" >> $HGRCPATH $ hg init $ hg qinit $ hg qnew base.patch $ echo aaa > a $ echo bbb > b $ echo ccc > c $ hg add a b c $ hg qrefresh $ readlink.py a a -> a not a symlink test replacing a file with a symlink $ hg qnew symlink.patch $ rm a $ ln -s b a $ hg qrefresh --git $ readlink.py a a -> b $ hg qpop popping symlink.patch now at: base.patch $ hg qpush applying symlink.patch now at: symlink.patch $ readlink.py a a -> b test updating a symlink $ rm a $ ln -s c a $ hg qnew --git -f updatelink $ readlink.py a a -> c $ hg qpop popping updatelink now at: symlink.patch $ hg qpush --debug applying updatelink patching file a committing files: a committing manifest committing changelog now at: updatelink $ readlink.py a a -> c $ hg st test replacing a symlink with a file $ ln -s c s $ hg add s $ hg qnew --git -f addlink $ rm s $ echo sss > s $ hg qnew --git -f replacelinkwithfile $ hg qpop popping replacelinkwithfile now at: addlink $ hg qpush applying replacelinkwithfile now at: replacelinkwithfile $ cat s sss $ hg st test symlink removal $ hg qnew removesl.patch $ hg rm a $ hg qrefresh --git $ hg qpop popping removesl.patch now at: replacelinkwithfile $ hg qpush applying removesl.patch now at: removesl.patch $ hg st -c C b C c C s replace broken symlink with another broken symlink $ ln -s linka linka $ hg add linka $ hg qnew link $ hg mv linka linkb $ rm linkb $ ln -s linkb linkb $ hg qnew movelink $ hg qpop popping movelink now at: link $ hg qpush applying movelink now at: movelink $ readlink.py linkb linkb -> linkb