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>
date Mon, 27 Sep 2021 12:09:15 +0200
parents 9d2b2df2c2ba
children 5105a9975407
line wrap: on
line source

# 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()