##// END OF EJS Templates
revlog: change generaldelta delta parent heuristic...
revlog: change generaldelta delta parent heuristic The old generaldelta heuristic was "if p1 (or p2) was closer than the last full text, use it, otherwise use prev". This was problematic when a repo contained multiple branches that were very different. If commits to branch A were pushed, and the last full text was branch B, it would generate a fulltext. Then if branch B was pushed, it would generate another fulltext. The problem is that the last fulltext (and delta'ing against `prev` in general) has no correlation with the contents of the incoming revision, and therefore will always have degenerate cases. According to the blame, that algorithm was chosen to minimize the chain length. Since there is already code that protects against that (the delta-vs-fulltext code), and since it has been improved since the original generaldelta algorithm went in (2011), I believe the chain length criteria will still be preserved. The new algorithm always diffs against p1 (or p2 if it's closer), unless the resulting delta will fail the delta-vs-fulltext check, in which case we delta against prev. Some before and after stats on manifest.d size. internal large repo old heuristic - 2.0 GB new heuristic - 1.2 GB mozilla-central old heuristic - 242 MB new heuristic - 261 MB The regression in mozilla central is due to the new heuristic choosing p2r as the delta when it's closer to the tip. Switching the algorithm to always prefer p1r brings the size back down (242 MB). This is result of the way in which mozilla does merges and pushes, and the result could easily swing the other direction in other repos (depending on if they merge X into Y or Y into X), but will never be as degenerate as before. I future patch will address the regression by introducing an optional, even more aggressive delta heuristic which will knock the mozilla manifest size down dramatically.

File last commit:

r25955:2c07c688 default
r26117:4dc5b51f default
Show More
i18n.py
96 lines | 3.3 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
# modelled after templater.templatepath:
if getattr(sys, 'frozen', None) is not None:
module = sys.executable
else:
module = __file__
_languages = None
if (os.name == 'nt'
and 'LANGUAGE' not in os.environ
and 'LC_ALL' not in os.environ
and 'LC_MESSAGES' not in os.environ
and 'LANG' not in os.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):
localedir = os.path.join(datapath, 'locale')
t = gettextmod.translation('hg', localedir, _languages, fallback=True)
global _ugettext
_ugettext = t.ugettext
_msgcache = {}
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
if message not in _msgcache:
if type(message) is 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 '' 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.
_msgcache[message] = u.encode(encoding.encoding, "replace")
except LookupError:
# An unknown encoding results in a LookupError.
_msgcache[message] = message
return _msgcache[message]
def _plain():
if 'HGPLAIN' not in os.environ and 'HGPLAINEXCEPT' not in os.environ:
return False
exceptions = os.environ.get('HGPLAINEXCEPT', '').strip().split(',')
return 'i18n' not in exceptions
if _plain():
_ = lambda message: message
else:
_ = gettext