revlog: optimize _chunkraw when startrev==endrev
In many cases, _chunkraw() is called with startrev==endrev. When
this is true, we can avoid an extra index lookup and some other
minor operations.
On the mozilla-unified repo, `hg perfrevlogchunks -c` says this
has the following impact:
! read w/ reused fd
! wall 0.371846 comb 0.370000 user 0.350000 sys 0.020000 (best of 27)
! wall 0.337930 comb 0.330000 user 0.300000 sys 0.030000 (best of 30)
! read batch w/ reused fd
! wall 0.014952 comb 0.020000 user 0.000000 sys 0.020000 (best of 197)
! wall 0.014866 comb 0.010000 user 0.000000 sys 0.010000 (best of 196)
So, we've gone from ~25x slower than batch to ~22.5x slower.
At this point, there's probably not much else we can do except
implement an optimized function in the index itself, including in C.
# py3kcompat.py - compatibility definitions for running hg in py3k
#
# Copyright 2010 Renato Cunha <renatoc@gmail.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 builtins
import numbers
Number = numbers.Number
def bytesformatter(format, args):
'''Custom implementation of a formatter for bytestrings.
This function currently relies on the string formatter to do the
formatting and always returns bytes objects.
>>> bytesformatter(20, 10)
0
>>> bytesformatter('unicode %s, %s!', ('string', 'foo'))
b'unicode string, foo!'
>>> bytesformatter(b'test %s', 'me')
b'test me'
>>> bytesformatter('test %s', 'me')
b'test me'
>>> bytesformatter(b'test %s', b'me')
b'test me'
>>> bytesformatter('test %s', b'me')
b'test me'
>>> bytesformatter('test %d: %s', (1, b'result'))
b'test 1: result'
'''
# The current implementation just converts from bytes to unicode, do
# what's needed and then convert the results back to bytes.
# Another alternative is to use the Python C API implementation.
if isinstance(format, Number):
# If the fixer erroneously passes a number remainder operation to
# bytesformatter, we just return the correct operation
return format % args
if isinstance(format, bytes):
format = format.decode('utf-8', 'surrogateescape')
if isinstance(args, bytes):
args = args.decode('utf-8', 'surrogateescape')
if isinstance(args, tuple):
newargs = []
for arg in args:
if isinstance(arg, bytes):
arg = arg.decode('utf-8', 'surrogateescape')
newargs.append(arg)
args = tuple(newargs)
ret = format % args
return ret.encode('utf-8', 'surrogateescape')
builtins.bytesformatter = bytesformatter
origord = builtins.ord
def fakeord(char):
if isinstance(char, int):
return char
return origord(char)
builtins.ord = fakeord
if __name__ == '__main__':
import doctest
doctest.testmod()