view mercurial/lsprofcalltree.py @ 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.

"""
lsprofcalltree.py - lsprof output which is readable by kcachegrind

Authors:
    * David Allouche <david <at> allouche.net>
    * Jp Calderone & Itamar Shtull-Trauring
    * Johan Dahlin

This software may be used and distributed according to the terms
of the GNU General Public License, incorporated herein by reference.
"""

def label(code):
    if isinstance(code, str):
        return '~' + code    # built-in functions ('~' sorts at the end)
    else:
        return '%s %s:%d' % (code.co_name,
                             code.co_filename,
                             code.co_firstlineno)

class KCacheGrind(object):
    def __init__(self, profiler):
        self.data = profiler.getstats()
        self.out_file = None

    def output(self, out_file):
        self.out_file = out_file
        print >> out_file, 'events: Ticks'
        self._print_summary()
        for entry in self.data:
            self._entry(entry)

    def _print_summary(self):
        max_cost = 0
        for entry in self.data:
            totaltime = int(entry.totaltime * 1000)
            max_cost = max(max_cost, totaltime)
        print >> self.out_file, 'summary: %d' % (max_cost,)

    def _entry(self, entry):
        out_file = self.out_file

        code = entry.code
        #print >> out_file, 'ob=%s' % (code.co_filename,)
        if isinstance(code, str):
            print >> out_file, 'fi=~'
        else:
            print >> out_file, 'fi=%s' % (code.co_filename,)
        print >> out_file, 'fn=%s' % (label(code),)

        inlinetime = int(entry.inlinetime * 1000)
        if isinstance(code, str):
            print >> out_file, '0 ', inlinetime
        else:
            print >> out_file, '%d %d' % (code.co_firstlineno, inlinetime)

        # recursive calls are counted in entry.calls
        if entry.calls:
            calls = entry.calls
        else:
            calls = []

        if isinstance(code, str):
            lineno = 0
        else:
            lineno = code.co_firstlineno

        for subentry in calls:
            self._subentry(lineno, subentry)
        print >> out_file

    def _subentry(self, lineno, subentry):
        out_file = self.out_file
        code = subentry.code
        #print >> out_file, 'cob=%s' % (code.co_filename,)
        print >> out_file, 'cfn=%s' % (label(code),)
        if isinstance(code, str):
            print >> out_file, 'cfi=~'
            print >> out_file, 'calls=%d 0' % (subentry.callcount,)
        else:
            print >> out_file, 'cfi=%s' % (code.co_filename,)
            print >> out_file, 'calls=%d %d' % (
                subentry.callcount, code.co_firstlineno)

        totaltime = int(subentry.totaltime * 1000)
        print >> out_file, '%d %d' % (lineno, totaltime)