Mercurial > hg
view mercurial/profiling.py @ 50336:cf4d2f31660d stable
chg: populate CHGHG if not set
Normally, chg determines which `hg` executable to use by first consulting the
`$CHGHG` and `$HG` environment variables, and if neither are present defaults
to the `hg` found in the user's `$PATH`. If built with the `HGPATHREL` compiler
flag, chg will instead assume that there exists an `hg` executable in the same
directory as the `chg` binary and attempt to use that.
This can cause problems in situations where there are multiple actively-used
Mercurial installations on the same system. When a `chg` client connects to a
running command server, the server process performs some basic validation to
determine whether a new command server needs to be spawned. These checks include
things like checking certain "sensitive" environment variables and config
sections, as well as checking whether the mtime of the extensions, hg's
`__version__.py` module, and the Python interpreter have changed.
Crucially, the command server doesn't explicitly check whether the executable it
is running from matches the executable that the `chg` client would have
otherwise invoked had there been no existing command server process. Without
`HGPATHREL`, this still gets implicitly checked during the validation step,
because the only way to specify an alternate hg executable (apart from `$PATH`)
is via the `$CHGHG` and `$HG` environment variables, both of which are checked.
With `HGPATHREL`, however, the command server has no way of knowing which hg
executable the client would have run. This means that a client located at
`/version_B/bin/chg` will happily connect to a command server running
`/version_A/bin/hg` instead of `/version_B/bin/hg` as expected. A simple
solution is to have the client set `$CHGHG` itself, which then allows the
command server's environment validation to work as intended.
I have tested this manually using two locally built hg installations and it
seems to work with no ill effects. That said, I'm not sure how to write an
automated test for this since the `chg` available to the tests isn't even built
with the `HGPATHREL` compiler flag to begin with.
author | Arun Kulshreshtha <akulshreshtha@janestreet.com> |
---|---|
date | Mon, 27 Mar 2023 17:30:14 -0400 |
parents | 642e31cb55f0 |
children | 18c8c18993f0 |
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# profiling.py - profiling functions # # Copyright 2016 Gregory Szorc <gregory.szorc@gmail.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. import contextlib from .i18n import _ from .pycompat import ( getattr, open, ) from . import ( encoding, error, extensions, pycompat, util, ) def _loadprofiler(ui, profiler): """load profiler extension. return profile method, or None on failure""" extname = profiler extensions.loadall(ui, whitelist=[extname]) try: mod = extensions.find(extname) except KeyError: return None else: return getattr(mod, 'profile', None) @contextlib.contextmanager def lsprofile(ui, fp): format = ui.config(b'profiling', b'format') field = ui.config(b'profiling', b'sort') limit = ui.configint(b'profiling', b'limit') climit = ui.configint(b'profiling', b'nested') if format not in [b'text', b'kcachegrind']: ui.warn(_(b"unrecognized profiling format '%s' - Ignored\n") % format) format = b'text' try: from . import lsprof except ImportError: raise error.Abort( _( b'lsprof not available - install from ' b'http://codespeak.net/svn/user/arigo/hack/misc/lsprof/' ) ) p = lsprof.Profiler() p.enable(subcalls=True) try: yield finally: p.disable() if format == b'kcachegrind': from . import lsprofcalltree calltree = lsprofcalltree.KCacheGrind(p) calltree.output(fp) else: # format == 'text' stats = lsprof.Stats(p.getstats()) stats.sort(pycompat.sysstr(field)) stats.pprint(limit=limit, file=fp, climit=climit) @contextlib.contextmanager def flameprofile(ui, fp): try: from flamegraph import flamegraph # pytype: disable=import-error except ImportError: raise error.Abort( _( b'flamegraph not available - install from ' b'https://github.com/evanhempel/python-flamegraph' ) ) # developer config: profiling.freq freq = ui.configint(b'profiling', b'freq') filter_ = None collapse_recursion = True thread = flamegraph.ProfileThread( fp, 1.0 / freq, filter_, collapse_recursion ) start_time = util.timer() try: thread.start() yield finally: thread.stop() thread.join() print( b'Collected %d stack frames (%d unique) in %2.2f seconds.' % ( util.timer() - start_time, thread.num_frames(), thread.num_frames(unique=True), ) ) @contextlib.contextmanager def statprofile(ui, fp): from . import statprof freq = ui.configint(b'profiling', b'freq') if freq > 0: # Cannot reset when profiler is already active. So silently no-op. if statprof.state.profile_level == 0: statprof.reset(freq) else: ui.warn(_(b"invalid sampling frequency '%s' - ignoring\n") % freq) track = ui.config( b'profiling', b'time-track', pycompat.iswindows and b'cpu' or b'real' ) statprof.start(mechanism=b'thread', track=track) try: yield finally: data = statprof.stop() profformat = ui.config(b'profiling', b'statformat') formats = { b'byline': statprof.DisplayFormats.ByLine, b'bymethod': statprof.DisplayFormats.ByMethod, b'hotpath': statprof.DisplayFormats.Hotpath, b'json': statprof.DisplayFormats.Json, b'chrome': statprof.DisplayFormats.Chrome, } if profformat in formats: displayformat = formats[profformat] else: ui.warn(_(b'unknown profiler output format: %s\n') % profformat) displayformat = statprof.DisplayFormats.Hotpath kwargs = {} def fraction(s): if isinstance(s, (float, int)): return float(s) if s.endswith(b'%'): v = float(s[:-1]) / 100 else: v = float(s) if 0 <= v <= 1: return v raise ValueError(s) if profformat == b'chrome': showmin = ui.configwith(fraction, b'profiling', b'showmin', 0.005) showmax = ui.configwith(fraction, b'profiling', b'showmax') kwargs.update(minthreshold=showmin, maxthreshold=showmax) elif profformat == b'hotpath': # inconsistent config: profiling.showmin limit = ui.configwith(fraction, b'profiling', b'showmin', 0.05) kwargs['limit'] = limit showtime = ui.configbool(b'profiling', b'showtime') kwargs['showtime'] = showtime statprof.display(fp, data=data, format=displayformat, **kwargs) class profile: """Start profiling. Profiling is active when the context manager is active. When the context manager exits, profiling results will be written to the configured output. """ def __init__(self, ui, enabled=True): self._ui = ui self._output = None self._fp = None self._fpdoclose = True self._flushfp = None self._profiler = None self._enabled = enabled self._entered = False self._started = False def __enter__(self): self._entered = True if self._enabled: self.start() return self def start(self): """Start profiling. The profiling will stop at the context exit. If the profiler was already started, this has no effect.""" if not self._entered: raise error.ProgrammingError(b'use a context manager to start') if self._started: return self._started = True profiler = encoding.environ.get(b'HGPROF') proffn = None if profiler is None: profiler = self._ui.config(b'profiling', b'type') if profiler not in (b'ls', b'stat', b'flame'): # try load profiler from extension with the same name proffn = _loadprofiler(self._ui, profiler) if proffn is None: self._ui.warn( _(b"unrecognized profiler '%s' - ignored\n") % profiler ) profiler = b'stat' self._output = self._ui.config(b'profiling', b'output') try: if self._output == b'blackbox': self._fp = util.stringio() elif self._output: path = util.expandpath(self._output) self._fp = open(path, b'wb') elif pycompat.iswindows: # parse escape sequence by win32print() class uifp: def __init__(self, ui): self._ui = ui def write(self, data): self._ui.write_err(data) def flush(self): self._ui.flush() self._fpdoclose = False self._fp = uifp(self._ui) else: self._fpdoclose = False self._fp = self._ui.ferr # Ensure we've flushed fout before writing to ferr. self._flushfp = self._ui.fout if proffn is not None: pass elif profiler == b'ls': proffn = lsprofile elif profiler == b'flame': proffn = flameprofile else: proffn = statprofile self._profiler = proffn(self._ui, self._fp) self._profiler.__enter__() except: # re-raises self._closefp() raise def __exit__(self, exception_type, exception_value, traceback): propagate = None if self._profiler is not None: self._uiflush() propagate = self._profiler.__exit__( exception_type, exception_value, traceback ) if self._output == b'blackbox': val = b'Profile:\n%s' % self._fp.getvalue() # ui.log treats the input as a format string, # so we need to escape any % signs. val = val.replace(b'%', b'%%') self._ui.log(b'profile', val) self._closefp() return propagate def _closefp(self): if self._fpdoclose and self._fp is not None: self._fp.close() def _uiflush(self): if self._flushfp: self._flushfp.flush()