tests/killdaemons.py

performance: speedup computation of extinct revisions

In their current state, revset calls can be very costly, as we test
predicates on the entire repository.

This change drops revset calls in favor of direct testing of the phase
of changesets.

Performance test on my Mercurial checkout
- 19857 total changesets,
- 1584 obsolete changesets,
- 13310 obsolescence markers.

Before:
  ! extinct
  ! wall 0.015124

After:
  ! extinct
  ! wall 0.009424

Performance test on a Mozilla central checkout:
- 117293 total changesets,
- 1 obsolete changeset,
- 1 obsolescence marker.

Before:
  ! extinct
  ! wall 0.032844

After:
  ! extinct
  ! wall 0.000066

#!/usr/bin/env python

import os, sys, time, errno, signal

if os.name =='nt':
    import ctypes
    def kill(pid, logfn, tryhard=True):
        logfn('# Killing daemon process %d' % pid)
        PROCESS_TERMINATE = 1
        handle = ctypes.windll.kernel32.OpenProcess(
                PROCESS_TERMINATE, False, pid)
        ctypes.windll.kernel32.TerminateProcess(handle, -1)
        ctypes.windll.kernel32.CloseHandle(handle)
else:
    def kill(pid, logfn, tryhard=True):
        try:
            os.kill(pid, 0)
            logfn('# Killing daemon process %d' % pid)
            os.kill(pid, signal.SIGTERM)
            if tryhard:
                for i in range(10):
                    time.sleep(0.05)
                    os.kill(pid, 0)
            else:
                time.sleep(0.1)
                os.kill(pid, 0)
            logfn('# Daemon process %d is stuck - really killing it' % pid)
            os.kill(pid, signal.SIGKILL)
        except OSError, err:
            if err.errno != errno.ESRCH:
                raise

def killdaemons(pidfile, tryhard=True, remove=False, logfn=None):
    if not logfn:
        logfn = lambda s: s
    # Kill off any leftover daemon processes
    try:
        fp = open(pidfile)
        for line in fp:
            try:
                pid = int(line)
            except ValueError:
                continue
            kill(pid, logfn, tryhard)
        fp.close()
        if remove:
            os.unlink(pidfile)
    except IOError:
        pass

if __name__ == '__main__':
    path, = sys.argv[1:]
    killdaemons(path)