wireprotoframing: buffer emitted data to reduce frame count
An upcoming commit introduces a wire protocol command that can emit
hundreds of thousands of small objects. Without a buffering layer,
we would emit a single, small frame for every object. Performance
profiling revealed this to be a source of significant overhead for
both client and server.
This commit introduces a very crude buffering layer so that we emit
fewer, bigger frames in such a scenario. This code will likely get
rewritten in the future to be part of the streams API, as we'll
need a similar strategy for compressing data. I don't want to think
about it too much at the moment though.
server
before: user 32.500+0.000 sys 1.160+0.000
after: user 20.230+0.010 sys 0.180+0.000
client
before: user 133.400+0.000 sys 93.120+0.000
after: user 68.370+0.000 sys 32.950+0.000
This appears to indicate we have significant overhead in the frame
processing code on both client and server. It might be worth profiling
that at some point...
Differential Revision: https://phab.mercurial-scm.org/D4473
#!/usr/bin/env python
#
# runrst - register custom roles and run correct writer
#
# Copyright 2010 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.
"""usage: %s WRITER args...
where WRITER is the name of a Docutils writer such as 'html' or 'manpage'
"""
from __future__ import absolute_import
import sys
try:
import docutils.core as core
import docutils.nodes as nodes
import docutils.utils as utils
import docutils.parsers.rst.roles as roles
except ImportError:
sys.stderr.write("abort: couldn't generate documentation: docutils "
"module is missing\n")
sys.stderr.write("please install python-docutils or see "
"http://docutils.sourceforge.net/\n")
sys.exit(-1)
def role_hg(name, rawtext, text, lineno, inliner,
options={}, content=[]):
text = "hg " + utils.unescape(text)
linktext = nodes.literal(rawtext, text)
parts = text.split()
cmd, args = parts[1], parts[2:]
refuri = "hg.1.html#%s" % cmd
if cmd == 'help' and args:
if args[0] == 'config':
# :hg:`help config`
refuri = "hgrc.5.html"
elif args[0].startswith('config.'):
# :hg:`help config.SECTION...`
refuri = "hgrc.5.html#%s" % args[0].split('.', 2)[1]
elif len(args) >= 2 and args[0] == '-c':
# :hg:`help -c COMMAND ...` is equivalent to :hg:`COMMAND`
# (mainly for :hg:`help -c config`)
refuri = "hg.1.html#%s" % args[1]
else:
refuri = "hg.1.html#%s" % args[0]
node = nodes.reference(rawtext, '', linktext,
refuri=refuri)
return [node], []
roles.register_local_role("hg", role_hg)
if __name__ == "__main__":
if len(sys.argv) < 2:
sys.stderr.write(__doc__ % sys.argv[0])
sys.exit(1)
writer = sys.argv[1]
del sys.argv[1]
core.publish_cmdline(writer_name=writer)