##// END OF EJS Templates
parsers: inline fields of dirstate values in C version...
parsers: inline fields of dirstate values in C version Previously, while unpacking the dirstate we'd create 3-4 new CPython objects for most dirstate values: - the state is a single character string, which is pooled by CPython - the mode is a new object if it isn't 0 due to being in the lookup set - the size is a new object if it is greater than 255 - the mtime is a new object if it isn't -1 due to being in the lookup set - the tuple to contain them all In some cases such as regular hg status, we actually look at all the objects. In other cases like hg add, hg status for a subdirectory, or hg status with the third-party hgwatchman enabled, we look at almost none of the objects. This patch eliminates most object creation in these cases by defining a custom C struct that is exposed to Python with an interface similar to a tuple. Only when tuple elements are actually requested are the respective objects created. The gains, where they're expected, are significant. The following tests are run against a working copy with over 270,000 files. parse_dirstate becomes significantly faster: $ hg perfdirstate before: wall 0.186437 comb 0.180000 user 0.160000 sys 0.020000 (best of 35) after: wall 0.093158 comb 0.100000 user 0.090000 sys 0.010000 (best of 95) and as a result, several commands benefit: $ time hg status # with hgwatchman enabled before: 0.42s user 0.14s system 99% cpu 0.563 total after: 0.34s user 0.12s system 99% cpu 0.471 total $ time hg add new-file before: 0.85s user 0.18s system 99% cpu 1.033 total after: 0.76s user 0.17s system 99% cpu 0.931 total There is a slight regression in regular status performance, but this is fixed in an upcoming patch.

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diffhelpers.py
60 lines | 1.5 KiB | text/x-python | PythonLexer
# diffhelpers.py - pure Python implementation of diffhelpers.c
#
# Copyright 2009 Matt Mackall <mpm@selenic.com> 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.
def addlines(fp, hunk, lena, lenb, a, b):
while True:
todoa = lena - len(a)
todob = lenb - len(b)
num = max(todoa, todob)
if num == 0:
break
for i in xrange(num):
s = fp.readline()
c = s[0]
if s == "\\ No newline at end of file\n":
fix_newline(hunk, a, b)
continue
if c == "\n":
# Some patches may be missing the control char
# on empty lines. Supply a leading space.
s = " \n"
hunk.append(s)
if c == "+":
b.append(s[1:])
elif c == "-":
a.append(s)
else:
b.append(s[1:])
a.append(s)
return 0
def fix_newline(hunk, a, b):
l = hunk[-1]
# tolerate CRLF in last line
if l.endswith('\r\n'):
hline = l[:-2]
else:
hline = l[:-1]
c = hline[0]
if c in " +":
b[-1] = hline[1:]
if c in " -":
a[-1] = hline
hunk[-1] = hline
return 0
def testhunk(a, b, bstart):
alen = len(a)
blen = len(b)
if alen > blen - bstart:
return -1
for i in xrange(alen):
if a[i][1:] != b[i + bstart]:
return -1
return 0