##// END OF EJS Templates
snapshot: search for unrelated but reusable full-snapshot...
snapshot: search for unrelated but reusable full-snapshot # New Strategy Step: Reusing Snapshot Outside Of Parents' Chain. If no suitable bases were found in the parent's chains, see if we could reuse a full snapshot not directly related to the current revision. Such search can be expensive, so we only search for snapshots appended to the revlog *after* the bases used by the parents of the current revision (the one we just tested). We assume the parent's bases were created because the previous snapshots were unsuitable, so there are low odds they would be useful now. This search gives a chance to reuse a delta chain unrelated to the current revision. Without this re-use, topological branches would keep reopening new full chains. Creating more and more snapshots as the repository grow. In repositories with many topological branches, the lack of delta reuse can create too many snapshots reducing overall compression to nothing. This results in a very large repository and other usability issues. For now, we still focus on creating level-1 snapshots. However, this principle will play a large part in how we avoid snapshot explosion once we have more snapshot levels. # Effects On The Test Repository In the test repository we created, we can see the beneficial effect of such reuse. We need very few level-0 snapshots and the overall revlog size has decreased. The `hg debugrevlog` call, show a "lvl-2" snapshot. It comes from the existing delta logic using the `prev` revision (revlog's tip) as the base. In this specific case, it turns out the tip was a level-1 snapshot. This is a coincidence that can be ignored. Finding and testing against all these unrelated snapshots can have a performance impact at write time. We currently focus on building good deltas chain we build. Performance concern will be dealt with later in another series.

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i18n.py
105 lines | 3.6 KiB | text/x-python | PythonLexer
# i18n.py - internationalization support for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import gettext as gettextmod
import locale
import os
import sys
from . import (
encoding,
pycompat,
)
# modelled after templater.templatepath:
if getattr(sys, 'frozen', None) is not None:
module = pycompat.sysexecutable
else:
module = pycompat.fsencode(__file__)
_languages = None
if (pycompat.iswindows
and 'LANGUAGE' not in encoding.environ
and 'LC_ALL' not in encoding.environ
and 'LC_MESSAGES' not in encoding.environ
and 'LANG' not in encoding.environ):
# Try to detect UI language by "User Interface Language Management" API
# if no locale variables are set. Note that locale.getdefaultlocale()
# uses GetLocaleInfo(), which may be different from UI language.
# (See http://msdn.microsoft.com/en-us/library/dd374098(v=VS.85).aspx )
try:
import ctypes
langid = ctypes.windll.kernel32.GetUserDefaultUILanguage()
_languages = [locale.windows_locale[langid]]
except (ImportError, AttributeError, KeyError):
# ctypes not found or unknown langid
pass
_ugettext = None
def setdatapath(datapath):
datapath = pycompat.fsdecode(datapath)
localedir = os.path.join(datapath, r'locale')
t = gettextmod.translation(r'hg', localedir, _languages, fallback=True)
global _ugettext
try:
_ugettext = t.ugettext
except AttributeError:
_ugettext = t.gettext
_msgcache = {} # encoding: {message: translation}
def gettext(message):
"""Translate message.
The message is looked up in the catalog to get a Unicode string,
which is encoded in the local encoding before being returned.
Important: message is restricted to characters in the encoding
given by sys.getdefaultencoding() which is most likely 'ascii'.
"""
# If message is None, t.ugettext will return u'None' as the
# translation whereas our callers expect us to return None.
if message is None or not _ugettext:
return message
cache = _msgcache.setdefault(encoding.encoding, {})
if message not in cache:
if type(message) is pycompat.unicode:
# goofy unicode docstrings in test
paragraphs = message.split(u'\n\n')
else:
paragraphs = [p.decode("ascii") for p in message.split('\n\n')]
# Be careful not to translate the empty string -- it holds the
# meta data of the .po file.
u = u'\n\n'.join([p and _ugettext(p) or u'' for p in paragraphs])
try:
# encoding.tolocal cannot be used since it will first try to
# decode the Unicode string. Calling u.decode(enc) really
# means u.encode(sys.getdefaultencoding()).decode(enc). Since
# the Python encoding defaults to 'ascii', this fails if the
# translated string use non-ASCII characters.
encodingstr = pycompat.sysstr(encoding.encoding)
cache[message] = u.encode(encodingstr, "replace")
except LookupError:
# An unknown encoding results in a LookupError.
cache[message] = message
return cache[message]
def _plain():
if ('HGPLAIN' not in encoding.environ
and 'HGPLAINEXCEPT' not in encoding.environ):
return False
exceptions = encoding.environ.get('HGPLAINEXCEPT', '').strip().split(',')
return 'i18n' not in exceptions
if _plain():
_ = lambda message: message
else:
_ = gettext