tags-fnode-cache: skip building a changectx in getfnode
Building a changectx object is costly, doing it just to retrieve the revision
number is suboptimal. Directly fetching the revision number from the changelog
provide a sizeable speedup to `hg debugupdatecache`.
### data-env-vars.name = mercurial-2018-08-01-zstd-sparse-revlog
# benchmark.name = debug-update-cache
# benchmark.variants.pre-state = warm
before: 0.213229 seconds
after: 0.165577 seconds (-22.35%)
# data-env-vars.name = mercurial-filtered-2019-11-22-zstd-sparse-revlog
before: 1.200383 seconds
after: 1.071618 seconds (-10.73%)
# data-env-vars.name = mozilla-central-2018-08-01-zstd-sparse-revlog
before: 1.465735 seconds
after: 0.923128 seconds (-37.02%)
# data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
before: 6.511771 seconds
after: 4.507316 seconds (-30.78%)
# data-env-vars.name = netbeans-2018-08-01-zstd-sparse-revlog
before: 1.023007 seconds
after: 0.645026 seconds (-36.95%)
# data-env-vars.name = pypy-2018-08-01-zstd-sparse-revlog
before: 0.381141 seconds
after: 0.268654 seconds (-29.51%)
#!/usr/bin/env python3
#
# mercurial - scalable distributed SCM
#
# Copyright 2005-2007 Olivia Mackall <olivia@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.
import os
import sys
libdir = '@LIBDIR@'
if libdir != '@' 'LIBDIR' '@':
if not os.path.isabs(libdir):
libdir = os.path.join(
os.path.dirname(os.path.realpath(__file__)), libdir
)
libdir = os.path.abspath(libdir)
sys.path.insert(0, libdir)
# Make `pip install --user ...` packages available to the official Windows
# build. Most py2 packaging installs directly into the system python
# environment, so no changes are necessary for other platforms. The Windows
# py2 package uses py2exe, which lacks a `site` module. Hardcode it according
# to the documentation.
if getattr(sys, 'frozen', None) == 'console_exe':
vi = sys.version_info
appdata = os.environ.get('APPDATA')
if appdata:
sys.path.append(
os.path.join(
appdata,
'Python',
'Python%d%d' % (vi[0], vi[1]),
'site-packages',
)
)
from hgdemandimport import tracing
with tracing.log('hg script'):
# enable importing on demand to reduce startup time
try:
import hgdemandimport
hgdemandimport.enable()
except ImportError:
sys.stderr.write(
"abort: couldn't find mercurial libraries in [%s]\n"
% ' '.join(sys.path)
)
sys.stderr.write("(check your install and PYTHONPATH)\n")
sys.exit(-1)
from mercurial import dispatch
dispatch.run()