Mercurial > hgsubversion
view README @ 889:7a98fbadcae9
revsets: huge speedups for fromsvn and svnrev
I have a hgsubversion repo that contains over 300,000 commits.
In that repo, this patch improves performance as follows:
hg --time log -r 'first(fromsvn())'
Before: 40.3 sec
After: 0.8 sec
hg --time log -r 'svnrev(350000)'
Before: 40.3 sec
After: 0.1 sec
Note: the performance of these revset implementations is very sensitive
to doing as little work as possible per line of the rev_map file.
I originally attempted to hide the file format details by hoisting the
parsing of each line up into RevMap.readmapfile, but the current less
abstract code is dramatically (10x or more) faster.
If the revmap file is missing, we error out and print a message
describing what to do.
| author | Bryan O'Sullivan <bryano@fb.com> |
|---|---|
| date | Sat, 12 May 2012 05:38:34 -0700 |
| parents | 050f03a3bdf5 |
| children | 3df6ed4e7561 |
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.. -*-restructuredtext-*- ============ hgsubversion ============ hgsubversion is an extension for Mercurial that allows using Mercurial as a Subversion client. At this point, hgsubversion is usable by users reasonably familiar with Mercurial as a VCS. It's not recommended to dive into hgsubversion as an introduction to Mercurial, since hgsubversion "bends the rules" a little and violates some of the typical assumptions of early Mercurial users. Installation ------------ You need to have either have Subversion 1.5 (or later) installed along with either Subvertpy 0.7.4 (or later) or the Subversion SWIG Python bindings. You need Mercurial 1.3 or later. .. _mercurial: http://selenic.com/repo/hg .. _mercurial-stable: http://selenic.com/repo/hg-stable .. _crew: http://hg.intevation.org/mercurial/crew .. _crew-stable: http://hg.intevation.org/mercurial/crew-stable If you are unfamiliar with installing Mercurial extensions, please see the UsingExtensions_ page in the Mercurial wiki. Look at the example for specifying an absolute path near the bottom of the page. You want to give the path to the top level of your clone of this repository. .. _UsingExtensions: http://mercurial.selenic.com/wiki/UsingExtensions Before using hgsubversion, I *strongly* encourage you to run the automated tests. Just use nose_ if you have it (or ``easy_install nose`` if you want it), or use ``python tests/run.py`` to run the suite with the conventional test runner. Note that because I use nose, there's a lot of stdout spew in the tests right now. The important part is that all the tests pass. .. _nose: http://code.google.com/p/python-nose/ You can check that hgsubversion is installed and properly activated using the following command:: $ hg version --svn Mercurial Distributed SCM (version ...) Copyright (C) 2005-2010 Matt Mackall <mpm@selenic.com> and others This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. hgsubversion: ... Subversion: ... bindings: Subvertpy ... If your bindings are listed as `SWIG`, please consider installing Subvertpy_. .. _Subvertpy: http://pypi.python.org/pypi/subvertpy Further Reading --------------- More information on how to use hgsubversion is available from within Mercurial in the `subversion` help topic. To view it, use:: $ hg help subversion The Restructured Text source for this topic is also available in the file ``hgsubverson/help/subversion.rst``.