view tests/revlog-formatv0.py @ 31467:08ecec297521

bdiff: use Python memory allocator in fixws

Python has its own memory allocation APIs. For allocations
<= 512 bytes, it allocates memory from arenas. This means that
average small allocations don't call the system allocator, which
makes them faster. Also, arena allocations cut down on memory
fragmentation, which can matter for performance in long-running
processes.

Another advantage of using the Python memory allocator is that
allocations are tracked by Python. This is a bigger deal in
Python 3, as modern versions of Python have some decent built-in
tools for examining memory usage, leaks, etc.

This patch converts a trivial malloc() + free() in the bdiff code
to use the Python allocator APIs. Since the object being
operated on is a line, chances are it will use an arena. So,
this could have a net positive impact on performance (although
I didn't measure it).

#!/usr/bin/env python
# Copyright 2010 Intevation GmbH
# Author(s):
# Thomas Arendsen Hein <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""Create a Mercurial repository in revlog format 0

changeset:   0:a1ef0b125355
tag:         tip
user:        user
date:        Thu Jan 01 00:00:00 1970 +0000
files:       empty
description:
empty file
"""

from __future__ import absolute_import
import os
import sys

files = [
    ('formatv0/.hg/00changelog.i',
     '000000000000004400000000000000000000000000000000000000'
     '000000000000000000000000000000000000000000000000000000'
     '0000a1ef0b125355d27765928be600cfe85784284ab3'),
    ('formatv0/.hg/00changelog.d',
     '756163613935613961356635353036303562366138343738336237'
     '61623536363738616436356635380a757365720a3020300a656d70'
     '74790a0a656d7074792066696c65'),
    ('formatv0/.hg/00manifest.i',
     '000000000000003000000000000000000000000000000000000000'
     '000000000000000000000000000000000000000000000000000000'
     '0000aca95a9a5f550605b6a84783b7ab56678ad65f58'),
    ('formatv0/.hg/00manifest.d',
     '75656d707479006238306465356431333837353835343163356630'
     '35323635616431343461623966613836643164620a'),
    ('formatv0/.hg/data/empty.i',
     '000000000000000000000000000000000000000000000000000000'
     '000000000000000000000000000000000000000000000000000000'
     '0000b80de5d138758541c5f05265ad144ab9fa86d1db'),
    ('formatv0/.hg/data/empty.d',
     ''),
]

def makedirs(name):
    """recursive directory creation"""
    parent = os.path.dirname(name)
    if parent:
        makedirs(parent)
    os.mkdir(name)

makedirs(os.path.join(*'formatv0/.hg/data'.split('/')))

for name, data in files:
    f = open(name, 'wb')
    f.write(data.decode('hex'))
    f.close()

sys.exit(0)