contrib/memory.py

obsolete: use C code for headrevs calculation

Previously, if there were filtered revs the repository could not use the C fast
path for computing the head revs in the changelog. This slowed down many
operations in large repositories.

This adds the ability to filter revs to the C fast path. This speeds up histedit
on repositories with filtered revs by 30% (13s to 9s). This could be improved
further by sorting the filtered revs and walking the sorted list while we walk
the changelog, but even this initial version that just calls __contains__ is
still massively faster.

The new C api is compatible for both new and old python clients, and the new
python client can call both new and old C apis.

# memory.py - track memory usage
#
# Copyright 2009 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''helper extension to measure memory usage

Reads current and peak memory usage from ``/proc/self/status`` and
prints it to ``stderr`` on exit.
'''

import atexit

def memusage(ui):
    """Report memory usage of the current process."""
    status = None
    result = {'peak': 0, 'rss': 0}
    try:
        # This will only work on systems with a /proc file system
        # (like Linux).
        status = open('/proc/self/status', 'r')
        for line in status:
            parts = line.split()
            key = parts[0][2:-1].lower()
            if key in result:
                result[key] = int(parts[1])
    finally:
        if status is not None:
            status.close()
    ui.write_err(", ".join(["%s: %.1f MiB" % (key, value / 1024.0)
                            for key, value in result.iteritems()]) + "\n")

def extsetup(ui):
    atexit.register(memusage, ui)