Mercurial > hg
view hgext/fastannotate/commands.py @ 48068:bf8837e3d7ce
dirstate: Remove the flat Rust DirstateMap implementation
Before this changeset we had two Rust implementations of `DirstateMap`.
This removes the "flat" DirstateMap so that the "tree" DirstateMap is always
used when Rust enabled. This simplifies the code a lot, and will enable
(in the next changeset) further removal of a trait abstraction.
This is a performance regression when:
* Rust is enabled, and
* The repository uses the legacy dirstate-v1 file format, and
* For `hg status`, unknown files are not listed (such as with `-mard`)
The regression is about 100 milliseconds for `hg status -mard` on a
semi-large repository (mozilla-central), from ~320ms to ~420ms.
We deem this to be small enough to be worth it.
The new dirstate-v2 is still experimental at this point, but we aim to
stabilize it (though not yet enable it by default for new repositories)
in Mercurial 6.0. Eventually, upgrating repositories to dirsate-v2 will
eliminate this regression (and enable other performance improvements).
# Background
The flat DirstateMap was introduced with the first Rust implementation of the
status algorithm. It works similarly to the previous Python + C one, with a
single `HashMap` that associates file paths to a `DirstateEntry` (where Python
has a dict).
We later added the tree DirstateMap where the root of the tree contains nodes
for files and directories that are directly at the root of the repository,
and nodes for directories can contain child nodes representing the files and
directly that *they* contain directly. The shape of this tree mirrors that of
the working directory in the filesystem. This enables the status algorithm to
traverse this tree in tandem with traversing the filesystem tree, which in
turns enables a more efficient algorithm.
Furthermore, the new dirstate-v2 file format is also based on a tree of the
same shape. The tree DirstateMap can access a dirstate-v2 file without parsing
it: binary data in a single large (possibly memory-mapped) bytes buffer is
traversed on demand. This allows `DirstateMap` creation to take `O(1)` time.
(Mutation works by creating new in-memory nodes with copy-on-write semantics,
and serialization is append-mostly.)
The tradeoff is that for "legacy" repositories that use the dirstate-v1 file
format, parsing that file into a tree DirstateMap takes more time. Profiling
shows that this time is dominated by `HashMap`. For a dirstate containing `F`
files with an average `D` directory depth, the flat DirstateMap does parsing
in `O(F)` number of HashMap operations but the tree DirstateMap in `O(F × D)`
operations, since each node has its own HashMap containing its child nodes.
This slower costs ~140ms on an old snapshot of mozilla-central, and ~80ms
on an old snapshot of the Netbeans repository.
The status algorithm is faster, but with `-mard` (when not listing unknown
files) it is typically not faster *enough* to compensate the slower parsing.
Both Rust implementations are always faster than the Python + C implementation
# Benchmark results
All benchmarks are run on changeset 98c0408324e6, with repositories that use
the dirstate-v1 file format, on a server with 4 CPU cores and 4 CPU threads
(no HyperThreading).
`hg status` benchmarks show wall clock times of the entire command as the
average and standard deviation of serveral runs, collected by
https://github.com/sharkdp/hyperfine and reformated.
Parsing benchmarks are wall clock time of the Rust function that converts a
bytes buffer of the dirstate file into the `DirstateMap` data structure as
used by the status algorithm. A single run each, collected by running
`hg status` this environment variable:
RUST_LOG=hg::dirstate::dirstate_map=trace,hg::dirstate_tree::dirstate_map=trace
Benchmark 1: Rust flat DirstateMap → Rust tree DirstateMap
hg status
mozilla-clean 562.3 ms ± 2.0 ms → 462.5 ms ± 0.6 ms 1.22 ± 0.00 times faster
mozilla-dirty 859.6 ms ± 2.2 ms → 719.5 ms ± 3.2 ms 1.19 ± 0.01 times faster
mozilla-ignored 558.2 ms ± 3.0 ms → 457.9 ms ± 2.9 ms 1.22 ± 0.01 times faster
mozilla-unknowns 859.4 ms ± 5.7 ms → 716.0 ms ± 4.7 ms 1.20 ± 0.01 times faster
netbeans-clean 336.5 ms ± 0.9 ms → 339.5 ms ± 0.4 ms 0.99 ± 0.00 times faster
netbeans-dirty 491.4 ms ± 1.6 ms → 475.1 ms ± 1.2 ms 1.03 ± 0.00 times faster
netbeans-ignored 343.7 ms ± 1.0 ms → 347.8 ms ± 0.4 ms 0.99 ± 0.00 times faster
netbeans-unknowns 484.3 ms ± 1.0 ms → 466.0 ms ± 1.2 ms 1.04 ± 0.00 times faster
hg status -mard
mozilla-clean 317.3 ms ± 0.6 ms → 422.5 ms ± 1.2 ms 0.75 ± 0.00 times faster
mozilla-dirty 315.4 ms ± 0.6 ms → 417.7 ms ± 1.1 ms 0.76 ± 0.00 times faster
mozilla-ignored 314.6 ms ± 0.6 ms → 417.4 ms ± 1.0 ms 0.75 ± 0.00 times faster
mozilla-unknowns 312.9 ms ± 0.9 ms → 417.3 ms ± 1.6 ms 0.75 ± 0.00 times faster
netbeans-clean 212.0 ms ± 0.6 ms → 283.6 ms ± 0.8 ms 0.75 ± 0.00 times faster
netbeans-dirty 211.4 ms ± 1.0 ms → 283.4 ms ± 1.6 ms 0.75 ± 0.01 times faster
netbeans-ignored 211.4 ms ± 0.9 ms → 283.9 ms ± 0.8 ms 0.74 ± 0.01 times faster
netbeans-unknowns 211.1 ms ± 0.6 ms → 283.4 ms ± 1.0 ms 0.74 ± 0.00 times faster
Parsing
mozilla-clean 38.4ms → 177.6ms
mozilla-dirty 38.8ms → 177.0ms
mozilla-ignored 38.8ms → 178.0ms
mozilla-unknowns 38.7ms → 176.9ms
netbeans-clean 16.5ms → 97.3ms
netbeans-dirty 16.5ms → 98.4ms
netbeans-ignored 16.9ms → 97.4ms
netbeans-unknowns 16.9ms → 96.3ms
Benchmark 2: Python + C dirstatemap → Rust tree DirstateMap
hg status
mozilla-clean 1261.0 ms ± 3.6 ms → 461.1 ms ± 0.5 ms 2.73 ± 0.00 times faster
mozilla-dirty 2293.4 ms ± 9.1 ms → 719.6 ms ± 3.6 ms 3.19 ± 0.01 times faster
mozilla-ignored 1240.4 ms ± 2.3 ms → 457.7 ms ± 1.9 ms 2.71 ± 0.00 times faster
mozilla-unknowns 2283.3 ms ± 9.0 ms → 719.7 ms ± 3.8 ms 3.17 ± 0.01 times faster
netbeans-clean 879.7 ms ± 3.5 ms → 339.9 ms ± 0.5 ms 2.59 ± 0.00 times faster
netbeans-dirty 1257.3 ms ± 4.7 ms → 474.6 ms ± 1.6 ms 2.65 ± 0.01 times faster
netbeans-ignored 943.9 ms ± 1.9 ms → 347.3 ms ± 1.1 ms 2.72 ± 0.00 times faster
netbeans-unknowns 1188.1 ms ± 5.0 ms → 465.2 ms ± 2.3 ms 2.55 ± 0.01 times faster
hg status -mard
mozilla-clean 903.2 ms ± 3.6 ms → 423.4 ms ± 2.2 ms 2.13 ± 0.01 times faster
mozilla-dirty 884.6 ms ± 4.5 ms → 417.3 ms ± 1.4 ms 2.12 ± 0.01 times faster
mozilla-ignored 881.9 ms ± 1.3 ms → 417.3 ms ± 0.8 ms 2.11 ± 0.00 times faster
mozilla-unknowns 878.5 ms ± 1.9 ms → 416.4 ms ± 0.9 ms 2.11 ± 0.00 times faster
netbeans-clean 434.9 ms ± 1.8 ms → 284.0 ms ± 0.8 ms 1.53 ± 0.01 times faster
netbeans-dirty 434.1 ms ± 0.8 ms → 283.1 ms ± 0.8 ms 1.53 ± 0.00 times faster
netbeans-ignored 431.7 ms ± 1.1 ms → 283.6 ms ± 1.8 ms 1.52 ± 0.01 times faster
netbeans-unknowns 433.0 ms ± 1.3 ms → 283.5 ms ± 0.7 ms 1.53 ± 0.00 times faster
Differential Revision: https://phab.mercurial-scm.org/D11516
author | Simon Sapin <simon.sapin@octobus.net> |
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date | Mon, 27 Sep 2021 12:09:15 +0200 |
parents | 9d2b2df2c2ba |
children | 5105a9975407 |
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# Copyright 2016-present Facebook. All Rights Reserved. # # commands: fastannotate commands # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import os from mercurial.i18n import _ from mercurial import ( commands, encoding, error, extensions, patch, pycompat, registrar, scmutil, util, ) from . import ( context as facontext, error as faerror, formatter as faformatter, ) cmdtable = {} command = registrar.command(cmdtable) def _matchpaths(repo, rev, pats, opts, aopts=facontext.defaultopts): """generate paths matching given patterns""" perfhack = repo.ui.configbool(b'fastannotate', b'perfhack') # disable perfhack if: # a) any walkopt is used # b) if we treat pats as plain file names, some of them do not have # corresponding linelog files if perfhack: # cwd related to reporoot reporoot = os.path.dirname(repo.path) reldir = os.path.relpath(encoding.getcwd(), reporoot) if reldir == b'.': reldir = b'' if any(opts.get(o[1]) for o in commands.walkopts): # a) perfhack = False else: # b) relpats = [ os.path.relpath(p, reporoot) if os.path.isabs(p) else p for p in pats ] # disable perfhack on '..' since it allows escaping from the repo if any( ( b'..' in f or not os.path.isfile( facontext.pathhelper(repo, f, aopts).linelogpath ) ) for f in relpats ): perfhack = False # perfhack: emit paths directory without checking with manifest # this can be incorrect if the rev dos not have file. if perfhack: for p in relpats: yield os.path.join(reldir, p) else: def bad(x, y): raise error.Abort(b"%s: %s" % (x, y)) ctx = scmutil.revsingle(repo, rev) m = scmutil.match(ctx, pats, opts, badfn=bad) for p in ctx.walk(m): yield p fastannotatecommandargs = { 'options': [ (b'r', b'rev', b'.', _(b'annotate the specified revision'), _(b'REV')), (b'u', b'user', None, _(b'list the author (long with -v)')), (b'f', b'file', None, _(b'list the filename')), (b'd', b'date', None, _(b'list the date (short with -q)')), (b'n', b'number', None, _(b'list the revision number (default)')), (b'c', b'changeset', None, _(b'list the changeset')), ( b'l', b'line-number', None, _(b'show line number at the first appearance'), ), ( b'e', b'deleted', None, _(b'show deleted lines (slow) (EXPERIMENTAL)'), ), ( b'', b'no-content', None, _(b'do not show file content (EXPERIMENTAL)'), ), (b'', b'no-follow', None, _(b"don't follow copies and renames")), ( b'', b'linear', None, _( b'enforce linear history, ignore second parent ' b'of merges (EXPERIMENTAL)' ), ), ( b'', b'long-hash', None, _(b'show long changeset hash (EXPERIMENTAL)'), ), ( b'', b'rebuild', None, _(b'rebuild cache even if it exists (EXPERIMENTAL)'), ), ] + commands.diffwsopts + commands.walkopts + commands.formatteropts, 'synopsis': _(b'[-r REV] [-f] [-a] [-u] [-d] [-n] [-c] [-l] FILE...'), 'inferrepo': True, } def fastannotate(ui, repo, *pats, **opts): """show changeset information by line for each file List changes in files, showing the revision id responsible for each line. This command is useful for discovering when a change was made and by whom. By default this command prints revision numbers. If you include --file, --user, or --date, the revision number is suppressed unless you also include --number. The default format can also be customized by setting fastannotate.defaultformat. Returns 0 on success. .. container:: verbose This command uses an implementation different from the vanilla annotate command, which may produce slightly different (while still reasonable) outputs for some cases. Unlike the vanilla anootate, fastannotate follows rename regardless of the existence of --file. For the best performance when running on a full repo, use -c, -l, avoid -u, -d, -n. Use --linear and --no-content to make it even faster. For the best performance when running on a shallow (remotefilelog) repo, avoid --linear, --no-follow, or any diff options. As the server won't be able to populate annotate cache when non-default options affecting results are used. """ if not pats: raise error.Abort(_(b'at least one filename or pattern is required')) # performance hack: filtered repo can be slow. unfilter by default. if ui.configbool(b'fastannotate', b'unfilteredrepo'): repo = repo.unfiltered() opts = pycompat.byteskwargs(opts) rev = opts.get(b'rev', b'.') rebuild = opts.get(b'rebuild', False) diffopts = patch.difffeatureopts( ui, opts, section=b'annotate', whitespace=True ) aopts = facontext.annotateopts( diffopts=diffopts, followmerge=not opts.get(b'linear', False), followrename=not opts.get(b'no_follow', False), ) if not any( opts.get(s) for s in [b'user', b'date', b'file', b'number', b'changeset'] ): # default 'number' for compatibility. but fastannotate is more # efficient with "changeset", "line-number" and "no-content". for name in ui.configlist( b'fastannotate', b'defaultformat', [b'number'] ): opts[name] = True ui.pager(b'fastannotate') template = opts.get(b'template') if template == b'json': formatter = faformatter.jsonformatter(ui, repo, opts) else: formatter = faformatter.defaultformatter(ui, repo, opts) showdeleted = opts.get(b'deleted', False) showlines = not bool(opts.get(b'no_content')) showpath = opts.get(b'file', False) # find the head of the main (master) branch master = ui.config(b'fastannotate', b'mainbranch') or rev # paths will be used for prefetching and the real annotating paths = list(_matchpaths(repo, rev, pats, opts, aopts)) # for client, prefetch from the server if util.safehasattr(repo, 'prefetchfastannotate'): repo.prefetchfastannotate(paths) for path in paths: result = lines = existinglines = None while True: try: with facontext.annotatecontext(repo, path, aopts, rebuild) as a: result = a.annotate( rev, master=master, showpath=showpath, showlines=(showlines and not showdeleted), ) if showdeleted: existinglines = {(l[0], l[1]) for l in result} result = a.annotatealllines( rev, showpath=showpath, showlines=showlines ) break except (faerror.CannotReuseError, faerror.CorruptedFileError): # happens if master moves backwards, or the file was deleted # and readded, or renamed to an existing name, or corrupted. if rebuild: # give up since we have tried rebuild already raise else: # try a second time rebuilding the cache (slow) rebuild = True continue if showlines: result, lines = result formatter.write(result, lines, existinglines=existinglines) formatter.end() _newopts = set() _knownopts = { opt[1].replace(b'-', b'_') for opt in (fastannotatecommandargs['options'] + commands.globalopts) } def _annotatewrapper(orig, ui, repo, *pats, **opts): """used by wrapdefault""" # we need this hack until the obsstore has 0.0 seconds perf impact if ui.configbool(b'fastannotate', b'unfilteredrepo'): repo = repo.unfiltered() # treat the file as text (skip the isbinary check) if ui.configbool(b'fastannotate', b'forcetext'): opts['text'] = True # check if we need to do prefetch (client-side) rev = opts.get('rev') if util.safehasattr(repo, 'prefetchfastannotate') and rev is not None: paths = list(_matchpaths(repo, rev, pats, pycompat.byteskwargs(opts))) repo.prefetchfastannotate(paths) return orig(ui, repo, *pats, **opts) def registercommand(): """register the fastannotate command""" name = b'fastannotate|fastblame|fa' command(name, helpbasic=True, **fastannotatecommandargs)(fastannotate) def wrapdefault(): """wrap the default annotate command, to be aware of the protocol""" extensions.wrapcommand(commands.table, b'annotate', _annotatewrapper) @command( b'debugbuildannotatecache', [(b'r', b'rev', b'', _(b'build up to the specific revision'), _(b'REV'))] + commands.walkopts, _(b'[-r REV] FILE...'), ) def debugbuildannotatecache(ui, repo, *pats, **opts): """incrementally build fastannotate cache up to REV for specified files If REV is not specified, use the config 'fastannotate.mainbranch'. If fastannotate.client is True, download the annotate cache from the server. Otherwise, build the annotate cache locally. The annotate cache will be built using the default diff and follow options and lives in '.hg/fastannotate/default'. """ opts = pycompat.byteskwargs(opts) rev = opts.get(b'REV') or ui.config(b'fastannotate', b'mainbranch') if not rev: raise error.Abort( _(b'you need to provide a revision'), hint=_(b'set fastannotate.mainbranch or use --rev'), ) if ui.configbool(b'fastannotate', b'unfilteredrepo'): repo = repo.unfiltered() ctx = scmutil.revsingle(repo, rev) m = scmutil.match(ctx, pats, opts) paths = list(ctx.walk(m)) if util.safehasattr(repo, 'prefetchfastannotate'): # client if opts.get(b'REV'): raise error.Abort(_(b'--rev cannot be used for client')) repo.prefetchfastannotate(paths) else: # server, or full repo progress = ui.makeprogress(_(b'building'), total=len(paths)) for i, path in enumerate(paths): progress.update(i) with facontext.annotatecontext(repo, path) as actx: try: if actx.isuptodate(rev): continue actx.annotate(rev, rev) except (faerror.CannotReuseError, faerror.CorruptedFileError): # the cache is broken (could happen with renaming so the # file history gets invalidated). rebuild and try again. ui.debug( b'fastannotate: %s: rebuilding broken cache\n' % path ) actx.rebuild() try: actx.annotate(rev, rev) except Exception as ex: # possibly a bug, but should not stop us from building # cache for other files. ui.warn( _( b'fastannotate: %s: failed to ' b'build cache: %r\n' ) % (path, ex) ) progress.complete()