##// END OF EJS Templates
merge: mark file gets as not thread safe (issue5933)...
merge: mark file gets as not thread safe (issue5933) In default installs, this has the effect of disabling the thread-based worker on Windows when manifesting files in the working directory. My measurements have shown that with revlog-based repositories, Mercurial spends a lot of CPU time in revlog code resolving file data. This ends up incurring a lot of context switching across threads and slows down `hg update` operations when going from an empty working directory to the tip of the repo. On mozilla-unified (246,351 files) on an i7-6700K (4+4 CPUs): before: 487s wall after: 360s wall (equivalent to worker.enabled=false) cpus=2: 379s wall Even with only 2 threads, the thread pool is still slower. The introduction of the thread-based worker (02b36e860e0b) states that it resulted in a "~50%" speedup for `hg sparse --enable-profile` and `hg sparse --disable-profile`. This disagrees with my measurement above. I theorize a few reasons for this: 1) Removal of files from the working directory is I/O - not CPU - bound and should benefit from a thread pool (unless I/O is insanely fast and the GIL release is near instantaneous). So tests like `hg sparse --enable-profile` may exercise deletion throughput and aren't good benchmarks for worker tasks that are CPU heavy. 2) The patch was authored by someone at Facebook. The results were likely measured against a repository using remotefilelog. And I believe that revision retrieval during working directory updates with remotefilelog will often use a remote store, thus being I/O and not CPU bound. This probably resulted in an overstated performance gain. Since there appears to be a need to enable the thread-based worker with some stores, I've made the flagging of file gets as thread safe configurable. I've made it experimental because I don't want to formalize a boolean flag for this option and because this attribute is best captured against the store implementation. But we don't have a proper store API for this yet. I'd rather cross this bridge later. It is possible there are revlog-based repositories that do benefit from a thread-based worker. I didn't do very comprehensive testing. If there are, we may want to devise a more proper algorithm for whether to use the thread-based worker, including possibly config options to limit the number of threads to use. But until I see evidence that justifies complexity, simplicity wins. Differential Revision: https://phab.mercurial-scm.org/D3963

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__init__.py
96 lines | 3.4 KiB | text/x-python | PythonLexer
# highlight - syntax highlighting in hgweb, based on Pygments
#
# Copyright 2008, 2009 Patrick Mezard <pmezard@gmail.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.
#
# The original module was split in an interface and an implementation
# file to defer pygments loading and speedup extension setup.
"""syntax highlighting for hgweb (requires Pygments)
It depends on the Pygments syntax highlighting library:
http://pygments.org/
There are the following configuration options::
[web]
pygments_style = <style> (default: colorful)
highlightfiles = <fileset> (default: size('<5M'))
highlightonlymatchfilename = <bool> (default False)
``highlightonlymatchfilename`` will only highlight files if their type could
be identified by their filename. When this is not enabled (the default),
Pygments will try very hard to identify the file type from content and any
match (even matches with a low confidence score) will be used.
"""
from __future__ import absolute_import
from . import highlight
from mercurial.hgweb import (
webcommands,
webutil,
)
from mercurial import (
extensions,
)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
def pygmentize(web, field, fctx, tmpl):
style = web.config('web', 'pygments_style', 'colorful')
expr = web.config('web', 'highlightfiles', "size('<5M')")
filenameonly = web.configbool('web', 'highlightonlymatchfilename', False)
ctx = fctx.changectx()
m = ctx.matchfileset(expr)
if m(fctx.path()):
highlight.pygmentize(field, fctx, style, tmpl,
guessfilenameonly=filenameonly)
def filerevision_highlight(orig, web, fctx):
mt = web.res.headers['Content-Type']
# only pygmentize for mimetype containing 'html' so we both match
# 'text/html' and possibly 'application/xhtml+xml' in the future
# so that we don't have to touch the extension when the mimetype
# for a template changes; also hgweb optimizes the case that a
# raw file is sent using rawfile() and doesn't call us, so we
# can't clash with the file's content-type here in case we
# pygmentize a html file
if 'html' in mt:
pygmentize(web, 'fileline', fctx, web.tmpl)
return orig(web, fctx)
def annotate_highlight(orig, web):
mt = web.res.headers['Content-Type']
if 'html' in mt:
fctx = webutil.filectx(web.repo, web.req)
pygmentize(web, 'annotateline', fctx, web.tmpl)
return orig(web)
def generate_css(web):
pg_style = web.config('web', 'pygments_style', 'colorful')
fmter = highlight.HtmlFormatter(style=pg_style)
web.res.headers['Content-Type'] = 'text/css'
web.res.setbodybytes(''.join([
'/* pygments_style = %s */\n\n' % pg_style,
fmter.get_style_defs(''),
]))
return web.res.sendresponse()
def extsetup():
# monkeypatch in the new version
extensions.wrapfunction(webcommands, '_filerevision',
filerevision_highlight)
extensions.wrapfunction(webcommands, 'annotate', annotate_highlight)
webcommands.highlightcss = generate_css
webcommands.__all__.append('highlightcss')