bookmark: add a test for a race condition on push
Bookmark pointing to unknown nodes are ignored. Later these ignored bookmarks
are dropped when writing the file back on disk. On paper, this behavior should
be fine, but with the current implementation, it can lead to unexpected
bookmark deletions.
In theory, to make sure writer as a consistent view, taking the lock also
invalidate bookmark data we already loaded into memory. However this
invalidation is incomplete. The data are stored in a `filecache` that preserve
them if the bookmark related file are untouched. In practice, the bookmark data
in memory also depends of the changelog content, because of the step checking
if the bookmarks refers to a node known to the changelog. So if the bookmark
data were loaded from an up to date bookmark file but filtered with an outdated
changelog file this go undetected.
This condition is fairly specific, but can occurs very often in practice. We
introduce a test recreating the situation. The test comes in an independant
changeset to show it actually reproduce the situation. The fix will come soon
after.
A large share of the initial investigation of this race condition was made by
Valentin Gatien-Baron <valentin.gatienbaron@gmail.com>.
test --time
$ hg --time help -q help 2>&1 | grep time > /dev/null
$ hg init a
$ cd a
Function to check that statprof ran
$ statprofran () {
> egrep 'Sample count:|No samples recorded' > /dev/null
> }
test --profile
$ hg st --profile 2>&1 | statprofran
Abreviated version
$ hg st --prof 2>&1 | statprofran
In alias
$ hg --config "alias.profst=status --profile" profst 2>&1 | statprofran
#if lsprof
$ prof='hg --config profiling.type=ls --profile'
$ $prof st 2>../out
$ grep CallCount ../out > /dev/null || cat ../out
$ $prof --config profiling.output=../out st
$ grep CallCount ../out > /dev/null || cat ../out
$ $prof --config profiling.output=blackbox --config extensions.blackbox= st
$ grep CallCount .hg/blackbox.log > /dev/null || cat .hg/blackbox.log
$ $prof --config profiling.format=text st 2>../out
$ grep CallCount ../out > /dev/null || cat ../out
$ echo "[profiling]" >> $HGRCPATH
$ echo "format=kcachegrind" >> $HGRCPATH
$ $prof st 2>../out
$ grep 'events: Ticks' ../out > /dev/null || cat ../out
$ $prof --config profiling.output=../out st
$ grep 'events: Ticks' ../out > /dev/null || cat ../out
#endif
#if lsprof serve
Profiling of HTTP requests works
$ $prof --config profiling.format=text --config profiling.output=../profile.log serve -d -p $HGPORT --pid-file ../hg.pid -A ../access.log
$ cat ../hg.pid >> $DAEMON_PIDS
$ hg -q clone -U http://localhost:$HGPORT ../clone
A single profile is logged because file logging doesn't append
$ grep CallCount ../profile.log | wc -l
\s*1 (re)
#endif
Install an extension that can sleep and guarantee a profiler has time to run
$ cat >> sleepext.py << EOF
> import time
> from mercurial import registrar
> cmdtable = {}
> command = registrar.command(cmdtable)
> @command(b'sleep', [], b'hg sleep')
> def sleep(ui, *args, **kwargs):
> time.sleep(0.1)
> EOF
$ cat >> $HGRCPATH << EOF
> [extensions]
> sleep = `pwd`/sleepext.py
> EOF
statistical profiler works
$ hg --profile sleep 2>../out
$ cat ../out | statprofran
Various statprof formatters work
$ hg --profile --config profiling.statformat=byline sleep 2>../out || cat ../out
$ head -n 3 ../out
% cumulative self
time seconds seconds name
* sleepext.py:*:sleep (glob)
$ cat ../out | statprofran
$ hg --profile --config profiling.statformat=bymethod sleep 2>../out || cat ../out
$ head -n 1 ../out
% cumulative self
$ cat ../out | statprofran
$ hg --profile --config profiling.statformat=hotpath sleep 2>../out || cat ../out
$ cat ../out | statprofran
$ hg --profile --config profiling.statformat=json sleep 2>../out || cat ../out
$ cat ../out
\[\[-?\d+.* (re)
statprof can be used as a standalone module
$ "$PYTHON" -m mercurial.statprof hotpath
must specify --file to load
[1]
$ cd ..
#if no-chg
profiler extension could be loaded before other extensions
$ cat > fooprof.py <<EOF
> from __future__ import absolute_import
> import contextlib
> import sys
> @contextlib.contextmanager
> def profile(ui, fp):
> print('fooprof: start profile')
> sys.stdout.flush()
> yield
> print('fooprof: end profile')
> sys.stdout.flush()
> def extsetup(ui):
> ui.write(b'fooprof: loaded\n')
> EOF
$ cat > otherextension.py <<EOF
> from __future__ import absolute_import
> def extsetup(ui):
> ui.write(b'otherextension: loaded\n')
> EOF
$ hg init b
$ cd b
$ cat >> .hg/hgrc <<EOF
> [extensions]
> other = $TESTTMP/otherextension.py
> fooprof = $TESTTMP/fooprof.py
> EOF
$ hg root
otherextension: loaded
fooprof: loaded
$TESTTMP/b
$ HGPROF=fooprof hg root --profile
fooprof: loaded
fooprof: start profile
otherextension: loaded
$TESTTMP/b
fooprof: end profile
$ HGPROF=other hg root --profile 2>&1 | head -n 2
otherextension: loaded
unrecognized profiler 'other' - ignored
$ HGPROF=unknown hg root --profile 2>&1 | head -n 1
unrecognized profiler 'unknown' - ignored
$ cd ..
#endif