mercurial/lsprof.py

Fix cold cache diff performance

cold cache diff performance has regressed in two ways.  localrepo.changes
has optimizations for diffing against the working dir parent that expect
node1 to be None.  commands.revpair() usage means that commands.dodiff()
never sends node1 == None.  This is fixed in localrepo.changes by checking
against the dirstate parents.

In the non-dirstate parents case, localrepo.changes does a loop comparing
files without first sorting the file names, leading to random access
across the disk.

# this is copied from the lsprof distro because somehow
# it is not installed by distutils
#
# small modifications made

import sys
from _lsprof import Profiler, profiler_entry, profiler_subentry

__all__ = ['profile', 'Stats']

def profile(f, *args, **kwds):
    """XXX docstring"""
    p = Profiler()
    p.enable(subcalls=True)
    try:
        ret = f(*args, **kwds)
    finally:
        p.disable()
    return ret, Stats(p.getstats())


class Stats(object):
    """XXX docstring"""

    def __init__(self, data):
        self.data = data

    def sort(self, crit="inlinetime"):
        """XXX docstring"""
        if crit not in profiler_entry.__dict__:
            raise ValueError, "Can't sort by %s" % crit
        self.data.sort(lambda b, a: cmp(getattr(a, crit),
                                        getattr(b, crit)))
        for e in self.data:
            if e.calls:
                e.calls.sort(lambda b, a: cmp(getattr(a, crit),
                                              getattr(b, crit)))

    def pprint(self, top=None, file=None, limit=None, climit=None):
        """XXX docstring"""
        if file is None:
            file = sys.stdout
        d = self.data
        if top is not None:
            d = d[:top]
        cols = "% 12s %11.4f %11.4f   %s\n"
        hcols = "% 12s %12s %12s %s\n"
        cols2 = "+%12s %11.4f %11.4f +  %s\n"
        file.write(hcols % ("CallCount", "Total(s)",
                            "Inline(s)", "module:lineno(function)"))
        count = 0
        for e in d:
            file.write(cols % (e.callcount, e.totaltime,
                               e.inlinetime, label(e.code)))
            count += 1
            if limit is not None and count == limit:
                return
            ccount = 0
            if e.calls:
                for se in e.calls:
                    file.write(cols % ("+%s" % se.callcount,
                                       se.totaltime, se.inlinetime,
                                       "+%s" % label(se.code)))
                    count += 1
                    ccount += 1
                    if limit is not None and count == limit:
                        return
                    if climit is not None and ccount == climit:
                        break

    def freeze(self):
        """Replace all references to code objects with string
        descriptions; this makes it possible to pickle the instance."""

        # this code is probably rather ickier than it needs to be!
        for i in range(len(self.data)):
            e = self.data[i]
            if not isinstance(e.code, str):
                self.data[i] = type(e)((label(e.code),) + e[1:])
                if e.calls:
                    for j in range(len(e.calls)):
                        se = e.calls[j]
                        if not isinstance(se.code, str):
                            e.calls[j] = type(se)((label(se.code),) + se[1:])

_fn2mod = {}

def label(code):
    if isinstance(code, str):
        return code
    try:
        mname = _fn2mod[code.co_filename]
    except KeyError:
        for k, v in sys.modules.iteritems():
            if v is None:
                continue
            if not hasattr(v, '__file__'):
                continue
            if not isinstance(v.__file__, str):
                continue
            if v.__file__.startswith(code.co_filename):
                mname = _fn2mod[code.co_filename] = k
                break
        else:
            mname = _fn2mod[code.co_filename] = '<%s>'%code.co_filename

    return '%s:%d(%s)' % (mname, code.co_firstlineno, code.co_name)


if __name__ == '__main__':
    import os
    sys.argv = sys.argv[1:]
    if not sys.argv:
        print >> sys.stderr, "usage: lsprof.py <script> <arguments...>"
        sys.exit(2)
    sys.path.insert(0, os.path.abspath(os.path.dirname(sys.argv[0])))
    stats = profile(execfile, sys.argv[0], globals(), locals())
    stats.sort()
    stats.pprint()