Mercurial > hg
view hgext/schemes.py @ 44363:f7459da77f23
nodemap: introduce an option to use mmap to read the nodemap mapping
The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.
This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).
Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:
Before:
* do not use the persistent nodemap
* use the CPython implementation of the index for nodemap
* use mmapping of the changelog index
After:
* use the MixedIndex Rust code, with the NodeTree object for nodemap access
(still in review)
* use the persistent nodemap data from disk
* access the persistent nodemap data through mmap
* use mmapping of the changelog index
The persistent nodemap greatly speed up most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.
Here are some numbers (in seconds) for the reference copy of mozilla-try:
Revset Before After abs-change speedup
-10000: 0.004622 0.005532 0.000910 × 0.83
-10: 0.000050 0.000132 0.000082 × 0.37
tip 0.000052 0.000085 0.000033 × 0.61
0 + (-10000:) 0.028222 0.005337 -0.022885 × 5.29
0 0.023521 0.000084 -0.023437 × 280.01
(-10000:) + 0 0.235539 0.005308 -0.230231 × 44.37
(-10:) + :9 0.232883 0.000180 -0.232703 ×1293.79
(-10000:) + (:99) 0.238735 0.005358 -0.233377 × 44.55
:99 + (-10000:) 0.317942 0.005593 -0.312349 × 56.84
:9 + (-10:) 0.313372 0.000179 -0.313193 ×1750.68
:9 0.316450 0.000143 -0.316307 ×2212.93
On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.
Here are some numbers (in seconds) for the reference copy of mercurial:
Revset Before After abs-change speedup
-10: 0.000065 0.000097 0.000032 × 0.67
tip 0.000063 0.000078 0.000015 × 0.80
0 0.000561 0.000079 -0.000482 × 7.10
-10000: 0.004609 0.003648 -0.000961 × 1.26
0 + (-10000:) 0.005023 0.003715 -0.001307 × 1.35
(-10:) + :9 0.002187 0.000108 -0.002079 ×20.25
(-10000:) + 0 0.006252 0.003716 -0.002536 × 1.68
(-10000:) + (:99) 0.006367 0.003707 -0.002660 × 1.71
:9 + (-10:) 0.003846 0.000110 -0.003736 ×34.96
:9 0.003854 0.000099 -0.003755 ×38.92
:99 + (-10000:) 0.007644 0.003778 -0.003866 × 2.02
Differential Revision: https://phab.mercurial-scm.org/D7894
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Tue, 11 Feb 2020 11:18:52 +0100 |
parents | c1ccefb513e4 |
children | 9d2b2df2c2ba |
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# Copyright 2009, Alexander Solovyov <piranha@piranha.org.ua> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. """extend schemes with shortcuts to repository swarms This extension allows you to specify shortcuts for parent URLs with a lot of repositories to act like a scheme, for example:: [schemes] py = http://code.python.org/hg/ After that you can use it like:: hg clone py://trunk/ Additionally there is support for some more complex schemas, for example used by Google Code:: [schemes] gcode = http://{1}.googlecode.com/hg/ The syntax is taken from Mercurial templates, and you have unlimited number of variables, starting with ``{1}`` and continuing with ``{2}``, ``{3}`` and so on. This variables will receive parts of URL supplied, split by ``/``. Anything not specified as ``{part}`` will be just appended to an URL. For convenience, the extension adds these schemes by default:: [schemes] py = http://hg.python.org/ bb = https://bitbucket.org/ bb+ssh = ssh://hg@bitbucket.org/ gcode = https://{1}.googlecode.com/hg/ kiln = https://{1}.kilnhg.com/Repo/ You can override a predefined scheme by defining a new scheme with the same name. """ from __future__ import absolute_import import os import re from mercurial.i18n import _ from mercurial import ( error, extensions, hg, pycompat, registrar, templater, util, ) cmdtable = {} command = registrar.command(cmdtable) # 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 = b'ships-with-hg-core' _partre = re.compile(br'{(\d+)\}') class ShortRepository(object): def __init__(self, url, scheme, templater): self.scheme = scheme self.templater = templater self.url = url try: self.parts = max(map(int, _partre.findall(self.url))) except ValueError: self.parts = 0 def __repr__(self): return b'<ShortRepository: %s>' % self.scheme def instance(self, ui, url, create, intents=None, createopts=None): url = self.resolve(url) return hg._peerlookup(url).instance( ui, url, create, intents=intents, createopts=createopts ) def resolve(self, url): # Should this use the util.url class, or is manual parsing better? try: url = url.split(b'://', 1)[1] except IndexError: raise error.Abort(_(b"no '://' in scheme url '%s'") % url) parts = url.split(b'/', self.parts) if len(parts) > self.parts: tail = parts[-1] parts = parts[:-1] else: tail = b'' context = dict((b'%d' % (i + 1), v) for i, v in enumerate(parts)) return b''.join(self.templater.process(self.url, context)) + tail def hasdriveletter(orig, path): if path: for scheme in schemes: if path.startswith(scheme + b':'): return False return orig(path) schemes = { b'py': b'http://hg.python.org/', b'bb': b'https://bitbucket.org/', b'bb+ssh': b'ssh://hg@bitbucket.org/', b'gcode': b'https://{1}.googlecode.com/hg/', b'kiln': b'https://{1}.kilnhg.com/Repo/', } def extsetup(ui): schemes.update(dict(ui.configitems(b'schemes'))) t = templater.engine(templater.parse) for scheme, url in schemes.items(): if ( pycompat.iswindows and len(scheme) == 1 and scheme.isalpha() and os.path.exists(b'%s:\\' % scheme) ): raise error.Abort( _( b'custom scheme %s:// conflicts with drive ' b'letter %s:\\\n' ) % (scheme, scheme.upper()) ) hg.schemes[scheme] = ShortRepository(url, scheme, t) extensions.wrapfunction(util, b'hasdriveletter', hasdriveletter) @command(b'debugexpandscheme', norepo=True) def expandscheme(ui, url, **opts): """given a repo path, provide the scheme-expanded path """ repo = hg._peerlookup(url) if isinstance(repo, ShortRepository): url = repo.resolve(url) ui.write(url + b'\n')