Mercurial > hg
view contrib/hgperf @ 39862:5a9ab91e0a45
revlog: new API to emit revision data
I recently refactored changegroup generation code to make it more
storage agnostic. I made significant progress. But there is still
a bit of work to be done. Specifically:
* Changegroup code is looking at low-level storage attributes to
influence sorting. Sorting should be done at the storage layer.
* The linknode lookup and sorting code for ellipsis is very
complicated.
* Linknodes are just generally wonky because e.g. file storage doesn't
know how to translate a linkrev to a changelog node.
* We regressed performance when introducing the request-response
objects.
Having thought about this problem a bit, I think I've come up with
a better interface for emitting revision deltas.
This commit defines and implements that interface. See the docstring
in repository.py for more info.
This API adds 3 notable features over the previous one.
First, it defers node ordering to the storage implementation in
the common case but allows overriding as necessary. We have a
facility for requesting an exact ordering (used in ellipsis
mode). We have another facility for storage order (used for changelog).
Second, we have an argument specifying assumptions about parents
revisions. This can be used to force a fulltext revision when we
don't know the receiver has a parent revision to delta against.
Third, we can control whether revision data is emitted. This makes
the API suitable as a generic "index data retrieval" API as well
as for producing revision deltas - possibly in the same operation!
The new API is much simpler: we no longer need a complicated "request"
object to encapsulate the delta generation request. I'm optimistic
this will restore performance loss associated with
emitrevisiondeltas().
Storage unit tests for the new API have been implemented.
Future commits will port existing consumers of emitrevisiondeltas()
to the new API then remove emitrevisiondeltas().
Differential Revision: https://phab.mercurial-scm.org/D4722
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Fri, 21 Sep 2018 14:28:21 -0700 |
parents | 163fa0aea71e |
children | 99e231afc29c |
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#!/usr/bin/env python # # hgperf - measure performance of Mercurial commands # # Copyright 2014 Matt Mackall <mpm@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. '''measure performance of Mercurial commands Using ``hgperf`` instead of ``hg`` measures performance of the target Mercurial command. For example, the execution below measures performance of :hg:`heads --topo`:: $ hgperf heads --topo All command output via ``ui`` is suppressed, and just measurement result is displayed: see also "perf" extension in "contrib". Costs of processing before dispatching to the command function like below are not measured:: - parsing command line (e.g. option validity check) - reading configuration files in But ``pre-`` and ``post-`` hook invocation for the target command is measured, even though these are invoked before or after dispatching to the command function, because these may be required to repeat execution of the target command correctly. ''' 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) # enable importing on demand to reduce startup time try: from mercurial import demandimport; demandimport.enable() except ImportError: import sys 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, util, ) def timer(func, title=None): results = [] begin = util.timer() count = 0 while True: ostart = os.times() cstart = util.timer() r = func() cstop = util.timer() ostop = os.times() count += 1 a, b = ostart, ostop results.append((cstop - cstart, b[0] - a[0], b[1]-a[1])) if cstop - begin > 3 and count >= 100: break if cstop - begin > 10 and count >= 3: break if title: sys.stderr.write("! %s\n" % title) if r: sys.stderr.write("! result: %s\n" % r) m = min(results) sys.stderr.write("! wall %f comb %f user %f sys %f (best of %d)\n" % (m[0], m[1] + m[2], m[1], m[2], count)) orgruncommand = dispatch.runcommand def runcommand(lui, repo, cmd, fullargs, ui, options, d, cmdpats, cmdoptions): ui.pushbuffer() lui.pushbuffer() timer(lambda : orgruncommand(lui, repo, cmd, fullargs, ui, options, d, cmdpats, cmdoptions)) ui.popbuffer() lui.popbuffer() dispatch.runcommand = runcommand dispatch.run()