perf: add threading capability to perfbdiff
Since we are releasing the GIL during diffing, it is interesting to see how a
thread pool would perform on diffing. We add a new `--threads` argument to
commands. Synchronizing the thread pool is a bit complex because we want to be
able to reuse it from one run to another.
On my computer (i7 with 4 cores + hyperthreading), I get the following data for
about 12000 revisions:
threads wall comb wall gain comb overhead
none 31.596715 31.59 0.00% 0.00%
1 31.621228 31.62 -0.08% 0.09%
2 16.406202 32.8 48.08% 3.83%
3 11.598334 34.76 63.29% 10.03%
4 9.205421 36.77 70.87% 16.40%
5 8.517604 42.51 73.04% 34.57%
6 7.94645 47.58 74.85% 50.62%
7 7.434972 51.92 76.47% 64.36%
8 7.070638 55.34 77.62% 75.18%
Compared to the feature disabled (threads=0), the overhead is negligible with
the threading code (threads=1), and the gain is already 48% with two threads.
#require test-repo
$ . "$TESTDIR/helpers-testrepo.sh"
Sanity check check-config.py
$ cat > testfile.py << EOF
> # Good
> foo = ui.config('ui', 'username')
> # Missing
> foo = ui.config('ui', 'doesnotexist')
> # Missing different type
> foo = ui.configint('ui', 'missingint')
> # Missing with default value
> foo = ui.configbool('ui', 'missingbool1', default=True)
> foo = ui.configbool('ui', 'missingbool2', False)
> # Inconsistent values for defaults.
> foo = ui.configint('ui', 'intdefault', default=1)
> foo = ui.configint('ui', 'intdefault', default=42)
> # Can suppress inconsistent value error
> foo = ui.configint('ui', 'intdefault2', default=1)
> # inconsistent config: ui.intdefault2
> foo = ui.configint('ui', 'intdefault2', default=42)
> EOF
$ cat > files << EOF
> mercurial/help/config.txt
> $TESTTMP/testfile.py
> EOF
$ cd "$TESTDIR"/..
$ $PYTHON contrib/check-config.py < $TESTTMP/files
foo = ui.configint('ui', 'intdefault', default=42)
conflict on ui.intdefault: ('int', '42') != ('int', '1')
at $TESTTMP/testfile.py:12:
undocumented: ui.doesnotexist (str)
undocumented: ui.intdefault (int) [42]
undocumented: ui.intdefault2 (int) [42]
undocumented: ui.missingbool1 (bool) [True]
undocumented: ui.missingbool2 (bool)
undocumented: ui.missingint (int)
New errors are not allowed. Warnings are strongly discouraged.
$ testrepohg files "set:(**.py or **.txt) - tests/**" | sed 's|\\|/|g' |
> $PYTHON contrib/check-config.py