Mercurial > hg
view tests/generate-working-copy-states.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 | 2372284d9457 |
children | 6000f5b25c9b |
line wrap: on
line source
# Helper script used for generating history and working copy files and content. # The file's name corresponds to its history. The number of changesets can # be specified on the command line. With 2 changesets, files with names like # content1_content2_content1-untracked are generated. The first two filename # segments describe the contents in the two changesets. The third segment # ("content1-untracked") describes the state in the working copy, i.e. # the file has content "content1" and is untracked (since it was previously # tracked, it has been forgotten). # # This script generates the filenames and their content, but it's up to the # caller to tell hg about the state. # # There are two subcommands: # filelist <numchangesets> # state <numchangesets> (<changeset>|wc) # # Typical usage: # # $ python $TESTDIR/generate-working-copy-states.py state 2 1 # $ hg addremove --similarity 0 # $ hg commit -m 'first' # # $ python $TESTDIR/generate-working-copy-states.py state 2 1 # $ hg addremove --similarity 0 # $ hg commit -m 'second' # # $ python $TESTDIR/generate-working-copy-states.py state 2 wc # $ hg addremove --similarity 0 # $ hg forget *_*_*-untracked # $ rm *_*_missing-* from __future__ import absolute_import, print_function import os import sys # Generates pairs of (filename, contents), where 'contents' is a list # describing the file's content at each revision (or in the working copy). # At each revision, it is either None or the file's actual content. When not # None, it may be either new content or the same content as an earlier # revisions, so all of (modified,clean,added,removed) can be tested. def generatestates(maxchangesets, parentcontents): depth = len(parentcontents) if depth == maxchangesets + 1: for tracked in (b'untracked', b'tracked'): filename = ( b"_".join( [ (content is None and b'missing' or content) for content in parentcontents ] ) + b"-" + tracked ) yield (filename, parentcontents) else: for content in {None, b'content' + (b"%d" % (depth + 1))} | set( parentcontents ): for combination in generatestates( maxchangesets, parentcontents + [content] ): yield combination # retrieve the command line arguments target = sys.argv[1] maxchangesets = int(sys.argv[2]) if target == 'state': depth = sys.argv[3] # sort to make sure we have stable output combinations = sorted(generatestates(maxchangesets, [])) # compute file content content = [] for filename, states in combinations: if target == 'filelist': print(filename.decode('ascii')) elif target == 'state': if depth == 'wc': # Make sure there is content so the file gets written and can be # tracked. It will be deleted outside of this script. content.append((filename, states[maxchangesets] or b'TOBEDELETED')) else: content.append((filename, states[int(depth) - 1])) else: print("unknown target:", target, file=sys.stderr) sys.exit(1) # write actual content for filename, data in content: if data is not None: f = open(filename, 'wb') f.write(data + b'\n') f.close() elif os.path.exists(filename): os.remove(filename)