Mercurial > hg
view mercurial/pathutil.py @ 42743:8c9a6adec67a
rust-discovery: using the children cache in add_missing
The DAG range computation often needs to get back to very old
revisions, and turns out to be disproportionately long, given
that the end goal is to remove the descendents of the given
missing revisons from the undecided set.
The fast iteration capabilities available in the Rust case make
it possible to avoid the DAG range entirely, at the cost of
precomputing the children cache, and to simply iterate on
children of the given missing revisions.
This is a case where staying on the same side of the interface
between the two languages has clear benefits.
On discoveries with initial undecided sets
small enough to bypass sampling entirely, the total cost of
computing the children cache and the subsequent iteration
becomes better than the Python + C counterpart, which relies on
reachableroots2.
For example, on a repo with more than one million revisions with
an initial undecided set of 11 elements, we get these figures:
Rust version with simple iteration
addcommons: 57.287us
first undecided computation: 184.278334ms
first children cache computation: 131.056us
addmissings iteration: 42.766us
first addinfo total: 185.24 ms
Python + C version
first addcommons: 0.29 ms
addcommons 0.21 ms
first undecided computation 191.35 ms
addmissings 45.75 ms
first addinfo total: 237.77 ms
On discoveries with large undecided sets, the initial price paid
makes the first addinfo slower than the Python + C version,
but that's more than compensated by the gain in sampling and
subsequent iterations.
Here's an extreme example with an undecided set of a million revisions:
Rust version:
first undecided computation: 293.842629ms
first children cache computation: 407.911297ms
addmissings iteration: 34.312869ms
first addinfo total: 776.02 ms
taking initial sample
query 2: sampling time: 1318.38 ms
query 2; still undecided: 1005013, sample size is: 200
addmissings: 143.062us
Python + C version:
first undecided computation 298.13 ms
addmissings 80.13 ms
first addinfo total: 399.62 ms
taking initial sample
query 2: sampling time: 3957.23 ms
query 2; still undecided: 1005013, sample size is: 200
addmissings 52.88 ms
Differential Revision: https://phab.mercurial-scm.org/D6428
author | Georges Racinet <georges.racinet@octobus.net> |
---|---|
date | Tue, 16 Apr 2019 01:16:39 +0200 |
parents | 21be76e07148 |
children | 2372284d9457 |
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from __future__ import absolute_import import errno import os import posixpath import stat from .i18n import _ from . import ( encoding, error, pycompat, util, ) def _lowerclean(s): return encoding.hfsignoreclean(s.lower()) class pathauditor(object): '''ensure that a filesystem path contains no banned components. the following properties of a path are checked: - ends with a directory separator - under top-level .hg - starts at the root of a windows drive - contains ".." More check are also done about the file system states: - traverses a symlink (e.g. a/symlink_here/b) - inside a nested repository (a callback can be used to approve some nested repositories, e.g., subrepositories) The file system checks are only done when 'realfs' is set to True (the default). They should be disable then we are auditing path for operation on stored history. If 'cached' is set to True, audited paths and sub-directories are cached. Be careful to not keep the cache of unmanaged directories for long because audited paths may be replaced with symlinks. ''' def __init__(self, root, callback=None, realfs=True, cached=False): self.audited = set() self.auditeddir = set() self.root = root self._realfs = realfs self._cached = cached self.callback = callback if os.path.lexists(root) and not util.fscasesensitive(root): self.normcase = util.normcase else: self.normcase = lambda x: x def __call__(self, path, mode=None): '''Check the relative path. path may contain a pattern (e.g. foodir/**.txt)''' path = util.localpath(path) normpath = self.normcase(path) if normpath in self.audited: return # AIX ignores "/" at end of path, others raise EISDIR. if util.endswithsep(path): raise error.Abort(_("path ends in directory separator: %s") % path) parts = util.splitpath(path) if (os.path.splitdrive(path)[0] or _lowerclean(parts[0]) in ('.hg', '.hg.', '') or pycompat.ospardir in parts): raise error.Abort(_("path contains illegal component: %s") % path) # Windows shortname aliases for p in parts: if "~" in p: first, last = p.split("~", 1) if last.isdigit() and first.upper() in ["HG", "HG8B6C"]: raise error.Abort(_("path contains illegal component: %s") % path) if '.hg' in _lowerclean(path): lparts = [_lowerclean(p.lower()) for p in parts] for p in '.hg', '.hg.': if p in lparts[1:]: pos = lparts.index(p) base = os.path.join(*parts[:pos]) raise error.Abort(_("path '%s' is inside nested repo %r") % (path, pycompat.bytestr(base))) normparts = util.splitpath(normpath) assert len(parts) == len(normparts) parts.pop() normparts.pop() prefixes = [] # It's important that we check the path parts starting from the root. # This means we won't accidentally traverse a symlink into some other # filesystem (which is potentially expensive to access). for i in range(len(parts)): prefix = pycompat.ossep.join(parts[:i + 1]) normprefix = pycompat.ossep.join(normparts[:i + 1]) if normprefix in self.auditeddir: continue if self._realfs: self._checkfs(prefix, path) prefixes.append(normprefix) if self._cached: self.audited.add(normpath) # only add prefixes to the cache after checking everything: we don't # want to add "foo/bar/baz" before checking if there's a "foo/.hg" self.auditeddir.update(prefixes) def _checkfs(self, prefix, path): """raise exception if a file system backed check fails""" curpath = os.path.join(self.root, prefix) try: st = os.lstat(curpath) except OSError as err: # EINVAL can be raised as invalid path syntax under win32. # They must be ignored for patterns can be checked too. if err.errno not in (errno.ENOENT, errno.ENOTDIR, errno.EINVAL): raise else: if stat.S_ISLNK(st.st_mode): msg = (_('path %r traverses symbolic link %r') % (pycompat.bytestr(path), pycompat.bytestr(prefix))) raise error.Abort(msg) elif (stat.S_ISDIR(st.st_mode) and os.path.isdir(os.path.join(curpath, '.hg'))): if not self.callback or not self.callback(curpath): msg = _("path '%s' is inside nested repo %r") raise error.Abort(msg % (path, pycompat.bytestr(prefix))) def check(self, path): try: self(path) return True except (OSError, error.Abort): return False def canonpath(root, cwd, myname, auditor=None): '''return the canonical path of myname, given cwd and root >>> def check(root, cwd, myname): ... a = pathauditor(root, realfs=False) ... try: ... return canonpath(root, cwd, myname, a) ... except error.Abort: ... return 'aborted' >>> def unixonly(root, cwd, myname, expected='aborted'): ... if pycompat.iswindows: ... return expected ... return check(root, cwd, myname) >>> def winonly(root, cwd, myname, expected='aborted'): ... if not pycompat.iswindows: ... return expected ... return check(root, cwd, myname) >>> winonly(b'd:\\\\repo', b'c:\\\\dir', b'filename') 'aborted' >>> winonly(b'c:\\\\repo', b'c:\\\\dir', b'filename') 'aborted' >>> winonly(b'c:\\\\repo', b'c:\\\\', b'filename') 'aborted' >>> winonly(b'c:\\\\repo', b'c:\\\\', b'repo\\\\filename', ... b'filename') 'filename' >>> winonly(b'c:\\\\repo', b'c:\\\\repo', b'filename', b'filename') 'filename' >>> winonly(b'c:\\\\repo', b'c:\\\\repo\\\\subdir', b'filename', ... b'subdir/filename') 'subdir/filename' >>> unixonly(b'/repo', b'/dir', b'filename') 'aborted' >>> unixonly(b'/repo', b'/', b'filename') 'aborted' >>> unixonly(b'/repo', b'/', b'repo/filename', b'filename') 'filename' >>> unixonly(b'/repo', b'/repo', b'filename', b'filename') 'filename' >>> unixonly(b'/repo', b'/repo/subdir', b'filename', b'subdir/filename') 'subdir/filename' ''' if util.endswithsep(root): rootsep = root else: rootsep = root + pycompat.ossep name = myname if not os.path.isabs(name): name = os.path.join(root, cwd, name) name = os.path.normpath(name) if auditor is None: auditor = pathauditor(root) if name != rootsep and name.startswith(rootsep): name = name[len(rootsep):] auditor(name) return util.pconvert(name) elif name == root: return '' else: # Determine whether `name' is in the hierarchy at or beneath `root', # by iterating name=dirname(name) until that causes no change (can't # check name == '/', because that doesn't work on windows). The list # `rel' holds the reversed list of components making up the relative # file name we want. rel = [] while True: try: s = util.samefile(name, root) except OSError: s = False if s: if not rel: # name was actually the same as root (maybe a symlink) return '' rel.reverse() name = os.path.join(*rel) auditor(name) return util.pconvert(name) dirname, basename = util.split(name) rel.append(basename) if dirname == name: break name = dirname # A common mistake is to use -R, but specify a file relative to the repo # instead of cwd. Detect that case, and provide a hint to the user. hint = None try: if cwd != root: canonpath(root, root, myname, auditor) relpath = util.pathto(root, cwd, '') if relpath.endswith(pycompat.ossep): relpath = relpath[:-1] hint = (_("consider using '--cwd %s'") % relpath) except error.Abort: pass raise error.Abort(_("%s not under root '%s'") % (myname, root), hint=hint) def normasprefix(path): '''normalize the specified path as path prefix Returned value can be used safely for "p.startswith(prefix)", "p[len(prefix):]", and so on. For efficiency, this expects "path" argument to be already normalized by "os.path.normpath", "os.path.realpath", and so on. See also issue3033 for detail about need of this function. >>> normasprefix(b'/foo/bar').replace(pycompat.ossep, b'/') '/foo/bar/' >>> normasprefix(b'/').replace(pycompat.ossep, b'/') '/' ''' d, p = os.path.splitdrive(path) if len(p) != len(pycompat.ossep): return path + pycompat.ossep else: return path # forward two methods from posixpath that do what we need, but we'd # rather not let our internals know that we're thinking in posix terms # - instead we'll let them be oblivious. join = posixpath.join dirname = posixpath.dirname