view hgext/remotefilelog/debugcommands.py @ 49517:52464a20add0

rhg: parallellize computation of [unsure_is_modified]

[unsure_is_modified] is called for every file for which we can't
determine its status based on its size and mtime alone.

In particular, this happens if the mtime of the file changes
without its contents changing.

Parallellizing this improves performance significantly when
we have many of these files.

Here's an example run (on a repo with ~400k files after dropping FS caches)

```
before:
real	0m53.901s
user	0m27.806s
sys	0m31.325s

after:
real	0m32.017s
user	0m34.277s
sys	1m26.250s
```

Another example run (a different FS):

```
before:
real	3m28.479s
user	0m31.800s
sys	0m25.324s

after:
real	0m29.751s
user	0m41.814s
sys	1m15.387s
```

# debugcommands.py - debug logic for remotefilelog
#
# Copyright 2013 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import os
import zlib

from mercurial.node import (
    bin,
    hex,
    sha1nodeconstants,
    short,
)
from mercurial.i18n import _
from mercurial.pycompat import open
from mercurial import (
    error,
    filelog,
    lock as lockmod,
    pycompat,
    revlog,
)
from mercurial.utils import hashutil
from . import (
    constants,
    datapack,
    fileserverclient,
    historypack,
    repack,
    shallowutil,
)


def debugremotefilelog(ui, path, **opts):
    decompress = opts.get('decompress')

    size, firstnode, mapping = parsefileblob(path, decompress)

    ui.status(_(b"size: %d bytes\n") % size)
    ui.status(_(b"path: %s \n") % path)
    ui.status(_(b"key: %s \n") % (short(firstnode)))
    ui.status(_(b"\n"))
    ui.status(
        _(b"%12s => %12s %13s %13s %12s\n")
        % (b"node", b"p1", b"p2", b"linknode", b"copyfrom")
    )

    queue = [firstnode]
    while queue:
        node = queue.pop(0)
        p1, p2, linknode, copyfrom = mapping[node]
        ui.status(
            _(b"%s => %s  %s  %s  %s\n")
            % (short(node), short(p1), short(p2), short(linknode), copyfrom)
        )
        if p1 != sha1nodeconstants.nullid:
            queue.append(p1)
        if p2 != sha1nodeconstants.nullid:
            queue.append(p2)


def buildtemprevlog(repo, file):
    # get filename key
    filekey = hex(hashutil.sha1(file).digest())
    filedir = os.path.join(repo.path, b'store/data', filekey)

    # sort all entries based on linkrev
    fctxs = []
    for filenode in os.listdir(filedir):
        if b'_old' not in filenode:
            fctxs.append(repo.filectx(file, fileid=bin(filenode)))

    fctxs = sorted(fctxs, key=lambda x: x.linkrev())

    # add to revlog
    temppath = repo.sjoin(b'data/temprevlog.i')
    if os.path.exists(temppath):
        os.remove(temppath)
    r = filelog.filelog(repo.svfs, b'temprevlog')

    class faket:
        def add(self, a, b, c):
            pass

    t = faket()
    for fctx in fctxs:
        if fctx.node() not in repo:
            continue

        p = fctx.filelog().parents(fctx.filenode())
        meta = {}
        if fctx.renamed():
            meta[b'copy'] = fctx.renamed()[0]
            meta[b'copyrev'] = hex(fctx.renamed()[1])

        r.add(fctx.data(), meta, t, fctx.linkrev(), p[0], p[1])

    return r


def debugindex(orig, ui, repo, file_=None, **opts):
    """dump the contents of an index file"""
    if (
        opts.get('changelog')
        or opts.get('manifest')
        or opts.get('dir')
        or not shallowutil.isenabled(repo)
        or not repo.shallowmatch(file_)
    ):
        return orig(ui, repo, file_, **opts)

    r = buildtemprevlog(repo, file_)

    # debugindex like normal
    format = opts.get(b'format', 0)
    if format not in (0, 1):
        raise error.Abort(_(b"unknown format %d") % format)

    generaldelta = r.version & revlog.FLAG_GENERALDELTA
    if generaldelta:
        basehdr = b' delta'
    else:
        basehdr = b'  base'

    if format == 0:
        ui.write(
            (
                b"   rev    offset  length " + basehdr + b" linkrev"
                b" nodeid       p1           p2\n"
            )
        )
    elif format == 1:
        ui.write(
            (
                b"   rev flag   offset   length"
                b"     size " + basehdr + b"   link     p1     p2"
                b"       nodeid\n"
            )
        )

    for i in r:
        node = r.node(i)
        if generaldelta:
            base = r.deltaparent(i)
        else:
            base = r.chainbase(i)
        if format == 0:
            try:
                pp = r.parents(node)
            except Exception:
                pp = [repo.nullid, repo.nullid]
            ui.write(
                b"% 6d % 9d % 7d % 6d % 7d %s %s %s\n"
                % (
                    i,
                    r.start(i),
                    r.length(i),
                    base,
                    r.linkrev(i),
                    short(node),
                    short(pp[0]),
                    short(pp[1]),
                )
            )
        elif format == 1:
            pr = r.parentrevs(i)
            ui.write(
                b"% 6d %04x % 8d % 8d % 8d % 6d % 6d % 6d % 6d %s\n"
                % (
                    i,
                    r.flags(i),
                    r.start(i),
                    r.length(i),
                    r.rawsize(i),
                    base,
                    r.linkrev(i),
                    pr[0],
                    pr[1],
                    short(node),
                )
            )


def debugindexdot(orig, ui, repo, file_):
    """dump an index DAG as a graphviz dot file"""
    if not shallowutil.isenabled(repo):
        return orig(ui, repo, file_)

    r = buildtemprevlog(repo, os.path.basename(file_)[:-2])

    ui.writenoi18n(b"digraph G {\n")
    for i in r:
        node = r.node(i)
        pp = r.parents(node)
        ui.write(b"\t%d -> %d\n" % (r.rev(pp[0]), i))
        if pp[1] != repo.nullid:
            ui.write(b"\t%d -> %d\n" % (r.rev(pp[1]), i))
    ui.write(b"}\n")


def verifyremotefilelog(ui, path, **opts):
    decompress = opts.get('decompress')

    for root, dirs, files in os.walk(path):
        for file in files:
            if file == b"repos":
                continue
            filepath = os.path.join(root, file)
            size, firstnode, mapping = parsefileblob(filepath, decompress)
            for p1, p2, linknode, copyfrom in mapping.values():
                if linknode == sha1nodeconstants.nullid:
                    actualpath = os.path.relpath(root, path)
                    key = fileserverclient.getcachekey(
                        b"reponame", actualpath, file
                    )
                    ui.status(
                        b"%s %s\n" % (key, os.path.relpath(filepath, path))
                    )


def _decompressblob(raw):
    return zlib.decompress(raw)


def parsefileblob(path, decompress):
    f = open(path, b"rb")
    try:
        raw = f.read()
    finally:
        f.close()

    if decompress:
        raw = _decompressblob(raw)

    offset, size, flags = shallowutil.parsesizeflags(raw)
    start = offset + size

    firstnode = None

    mapping = {}
    while start < len(raw):
        divider = raw.index(b'\0', start + 80)

        currentnode = raw[start : (start + 20)]
        if not firstnode:
            firstnode = currentnode

        p1 = raw[(start + 20) : (start + 40)]
        p2 = raw[(start + 40) : (start + 60)]
        linknode = raw[(start + 60) : (start + 80)]
        copyfrom = raw[(start + 80) : divider]

        mapping[currentnode] = (p1, p2, linknode, copyfrom)
        start = divider + 1

    return size, firstnode, mapping


def debugdatapack(ui, *paths, **opts):
    for path in paths:
        if b'.data' in path:
            path = path[: path.index(b'.data')]
        ui.write(b"%s:\n" % path)
        dpack = datapack.datapack(path)
        node = opts.get('node')
        if node:
            deltachain = dpack.getdeltachain(b'', bin(node))
            dumpdeltachain(ui, deltachain, **opts)
            return

        if opts.get('long'):
            hashformatter = hex
            hashlen = 42
        else:
            hashformatter = short
            hashlen = 14

        lastfilename = None
        totaldeltasize = 0
        totalblobsize = 0

        def printtotals():
            if lastfilename is not None:
                ui.write(b"\n")
            if not totaldeltasize or not totalblobsize:
                return
            difference = totalblobsize - totaldeltasize
            deltastr = b"%0.1f%% %s" % (
                (100.0 * abs(difference) / totalblobsize),
                (b"smaller" if difference > 0 else b"bigger"),
            )

            ui.writenoi18n(
                b"Total:%s%s  %s (%s)\n"
                % (
                    b"".ljust(2 * hashlen - len(b"Total:")),
                    (b'%d' % totaldeltasize).ljust(12),
                    (b'%d' % totalblobsize).ljust(9),
                    deltastr,
                )
            )

        bases = {}
        nodes = set()
        failures = 0
        for filename, node, deltabase, deltalen in dpack.iterentries():
            bases[node] = deltabase
            if node in nodes:
                ui.write((b"Bad entry: %s appears twice\n" % short(node)))
                failures += 1
            nodes.add(node)
            if filename != lastfilename:
                printtotals()
                name = b'(empty name)' if filename == b'' else filename
                ui.write(b"%s:\n" % name)
                ui.write(
                    b"%s%s%s%s\n"
                    % (
                        b"Node".ljust(hashlen),
                        b"Delta Base".ljust(hashlen),
                        b"Delta Length".ljust(14),
                        b"Blob Size".ljust(9),
                    )
                )
                lastfilename = filename
                totalblobsize = 0
                totaldeltasize = 0

            # Metadata could be missing, in which case it will be an empty dict.
            meta = dpack.getmeta(filename, node)
            if constants.METAKEYSIZE in meta:
                blobsize = meta[constants.METAKEYSIZE]
                totaldeltasize += deltalen
                totalblobsize += blobsize
            else:
                blobsize = b"(missing)"
            ui.write(
                b"%s  %s  %s%s\n"
                % (
                    hashformatter(node),
                    hashformatter(deltabase),
                    (b'%d' % deltalen).ljust(14),
                    pycompat.bytestr(blobsize),
                )
            )

        if filename is not None:
            printtotals()

        failures += _sanitycheck(ui, set(nodes), bases)
        if failures > 1:
            ui.warn((b"%d failures\n" % failures))
            return 1


def _sanitycheck(ui, nodes, bases):
    """
    Does some basic sanity checking on a packfiles with ``nodes`` ``bases`` (a
    mapping of node->base):

    - Each deltabase must itself be a node elsewhere in the pack
    - There must be no cycles
    """
    failures = 0
    for node in nodes:
        seen = set()
        current = node
        deltabase = bases[current]

        while deltabase != sha1nodeconstants.nullid:
            if deltabase not in nodes:
                ui.warn(
                    (
                        b"Bad entry: %s has an unknown deltabase (%s)\n"
                        % (short(node), short(deltabase))
                    )
                )
                failures += 1
                break

            if deltabase in seen:
                ui.warn(
                    (
                        b"Bad entry: %s has a cycle (at %s)\n"
                        % (short(node), short(deltabase))
                    )
                )
                failures += 1
                break

            current = deltabase
            seen.add(current)
            deltabase = bases[current]
        # Since ``node`` begins a valid chain, reset/memoize its base to nullid
        # so we don't traverse it again.
        bases[node] = sha1nodeconstants.nullid
    return failures


def dumpdeltachain(ui, deltachain, **opts):
    hashformatter = hex
    hashlen = 40

    lastfilename = None
    for filename, node, filename, deltabasenode, delta in deltachain:
        if filename != lastfilename:
            ui.write(b"\n%s\n" % filename)
            lastfilename = filename
        ui.write(
            b"%s  %s  %s  %s\n"
            % (
                b"Node".ljust(hashlen),
                b"Delta Base".ljust(hashlen),
                b"Delta SHA1".ljust(hashlen),
                b"Delta Length".ljust(6),
            )
        )

        ui.write(
            b"%s  %s  %s  %d\n"
            % (
                hashformatter(node),
                hashformatter(deltabasenode),
                hex(hashutil.sha1(delta).digest()),
                len(delta),
            )
        )


def debughistorypack(ui, path):
    if b'.hist' in path:
        path = path[: path.index(b'.hist')]
    hpack = historypack.historypack(path)

    lastfilename = None
    for entry in hpack.iterentries():
        filename, node, p1node, p2node, linknode, copyfrom = entry
        if filename != lastfilename:
            ui.write(b"\n%s\n" % filename)
            ui.write(
                b"%s%s%s%s%s\n"
                % (
                    b"Node".ljust(14),
                    b"P1 Node".ljust(14),
                    b"P2 Node".ljust(14),
                    b"Link Node".ljust(14),
                    b"Copy From",
                )
            )
            lastfilename = filename
        ui.write(
            b"%s  %s  %s  %s  %s\n"
            % (
                short(node),
                short(p1node),
                short(p2node),
                short(linknode),
                copyfrom,
            )
        )


def debugwaitonrepack(repo):
    with lockmod.lock(repack.repacklockvfs(repo), b"repacklock", timeout=-1):
        return


def debugwaitonprefetch(repo):
    with repo._lock(
        repo.svfs,
        b"prefetchlock",
        True,
        None,
        None,
        _(b'prefetching in %s') % repo.origroot,
    ):
        pass