view contrib/memory.py @ 26219:ae33fff17c1e

hg: establish a cache for localrepository instances

hgweb contained code for determining whether a cached localrepository
instance was up to date. This code was way too low-level to be in
hgweb.

This functionality has been moved to a new "cachedlocalrepo" class
in hg.py. The code has been changed slightly to facilitate use
inside a class. hgweb has been refactored to use the new API.

As part of this refactor, hgweb.repo no longer exists! We're very close
to using a distinct repo instance per thread.

The new cache records state when it is created. This intelligence
prevents an extra localrepository from being created on the first
hgweb request. This is why some redundant output from test-extension.t
has gone away.

# 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)