##// END OF EJS Templates
util: optimize cost auditing on insert...
util: optimize cost auditing on insert Calling popoldest() on insert with cost auditing enabled introduces significant overhead. The primary reason for this overhead is that popoldest() needs to walk the linked list to find the first non-empty node. When we call popoldest() within a loop, this can become quadratic. The performance impact is more pronounced on caches with large capacities. This commit effectively inlines the popoldest() call into _enforcecostlimit(). By doing so, we only do the backwards walk to find the first empty node once. However, we still may still perform this work on insert when the cache is near cost capacity. So this is only a partial performance win. $ hg perflrucachedict --size 4 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 100 ! gets w/ cost limit ! wall 0.598737 comb 0.590000 user 0.590000 sys 0.000000 (best of 17) ! inserts w/ cost limit ! wall 1.694282 comb 1.700000 user 1.700000 sys 0.000000 (best of 6) ! wall 1.659181 comb 1.650000 user 1.650000 sys 0.000000 (best of 7) ! mixed w/ cost limit ! wall 1.157655 comb 1.150000 user 1.150000 sys 0.000000 (best of 9) ! wall 1.139955 comb 1.140000 user 1.140000 sys 0.000000 (best of 9) $ hg perflrucachedict --size 1000 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 10000 ! gets w/ cost limit ! wall 0.598526 comb 0.600000 user 0.600000 sys 0.000000 (best of 17) ! wall 0.601993 comb 0.600000 user 0.600000 sys 0.000000 (best of 17) ! inserts w/ cost limit ! wall 37.838315 comb 37.840000 user 37.840000 sys 0.000000 (best of 3) ! wall 25.105273 comb 25.080000 user 25.080000 sys 0.000000 (best of 3) ! mixed w/ cost limit ! wall 18.060198 comb 18.060000 user 18.060000 sys 0.000000 (best of 3) ! wall 12.104470 comb 12.070000 user 12.070000 sys 0.000000 (best of 3) $ hg perflrucachedict --size 1000 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 10000 --mixedgetfreq 90 ! gets w/ cost limit ! wall 0.600024 comb 0.600000 user 0.600000 sys 0.000000 (best of 17) ! wall 0.614439 comb 0.620000 user 0.620000 sys 0.000000 (best of 17) ! inserts w/ cost limit ! wall 37.154547 comb 37.120000 user 37.120000 sys 0.000000 (best of 3) ! wall 25.963028 comb 25.960000 user 25.960000 sys 0.000000 (best of 3) ! mixed w/ cost limit ! wall 4.381602 comb 4.380000 user 4.370000 sys 0.010000 (best of 3) ! wall 3.174256 comb 3.170000 user 3.170000 sys 0.000000 (best of 4) Differential Revision: https://phab.mercurial-scm.org/D4504

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store.py
594 lines | 18.1 KiB | text/x-python | PythonLexer
# store.py - repository store handling for Mercurial
#
# Copyright 2008 Matt Mackall <mpm@selenic.com>
#
# 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 errno
import hashlib
import os
import stat
from .i18n import _
from . import (
error,
node,
policy,
pycompat,
util,
vfs as vfsmod,
)
parsers = policy.importmod(r'parsers')
# This avoids a collision between a file named foo and a dir named
# foo.i or foo.d
def _encodedir(path):
'''
>>> _encodedir(b'data/foo.i')
'data/foo.i'
>>> _encodedir(b'data/foo.i/bla.i')
'data/foo.i.hg/bla.i'
>>> _encodedir(b'data/foo.i.hg/bla.i')
'data/foo.i.hg.hg/bla.i'
>>> _encodedir(b'data/foo.i\\ndata/foo.i/bla.i\\ndata/foo.i.hg/bla.i\\n')
'data/foo.i\\ndata/foo.i.hg/bla.i\\ndata/foo.i.hg.hg/bla.i\\n'
'''
return (path
.replace(".hg/", ".hg.hg/")
.replace(".i/", ".i.hg/")
.replace(".d/", ".d.hg/"))
encodedir = getattr(parsers, 'encodedir', _encodedir)
def decodedir(path):
'''
>>> decodedir(b'data/foo.i')
'data/foo.i'
>>> decodedir(b'data/foo.i.hg/bla.i')
'data/foo.i/bla.i'
>>> decodedir(b'data/foo.i.hg.hg/bla.i')
'data/foo.i.hg/bla.i'
'''
if ".hg/" not in path:
return path
return (path
.replace(".d.hg/", ".d/")
.replace(".i.hg/", ".i/")
.replace(".hg.hg/", ".hg/"))
def _reserved():
''' characters that are problematic for filesystems
* ascii escapes (0..31)
* ascii hi (126..255)
* windows specials
these characters will be escaped by encodefunctions
'''
winreserved = [ord(x) for x in u'\\:*?"<>|']
for x in range(32):
yield x
for x in range(126, 256):
yield x
for x in winreserved:
yield x
def _buildencodefun():
'''
>>> enc, dec = _buildencodefun()
>>> enc(b'nothing/special.txt')
'nothing/special.txt'
>>> dec(b'nothing/special.txt')
'nothing/special.txt'
>>> enc(b'HELLO')
'_h_e_l_l_o'
>>> dec(b'_h_e_l_l_o')
'HELLO'
>>> enc(b'hello:world?')
'hello~3aworld~3f'
>>> dec(b'hello~3aworld~3f')
'hello:world?'
>>> enc(b'the\\x07quick\\xADshot')
'the~07quick~adshot'
>>> dec(b'the~07quick~adshot')
'the\\x07quick\\xadshot'
'''
e = '_'
xchr = pycompat.bytechr
asciistr = list(map(xchr, range(127)))
capitals = list(range(ord("A"), ord("Z") + 1))
cmap = dict((x, x) for x in asciistr)
for x in _reserved():
cmap[xchr(x)] = "~%02x" % x
for x in capitals + [ord(e)]:
cmap[xchr(x)] = e + xchr(x).lower()
dmap = {}
for k, v in cmap.iteritems():
dmap[v] = k
def decode(s):
i = 0
while i < len(s):
for l in pycompat.xrange(1, 4):
try:
yield dmap[s[i:i + l]]
i += l
break
except KeyError:
pass
else:
raise KeyError
return (lambda s: ''.join([cmap[s[c:c + 1]]
for c in pycompat.xrange(len(s))]),
lambda s: ''.join(list(decode(s))))
_encodefname, _decodefname = _buildencodefun()
def encodefilename(s):
'''
>>> encodefilename(b'foo.i/bar.d/bla.hg/hi:world?/HELLO')
'foo.i.hg/bar.d.hg/bla.hg.hg/hi~3aworld~3f/_h_e_l_l_o'
'''
return _encodefname(encodedir(s))
def decodefilename(s):
'''
>>> decodefilename(b'foo.i.hg/bar.d.hg/bla.hg.hg/hi~3aworld~3f/_h_e_l_l_o')
'foo.i/bar.d/bla.hg/hi:world?/HELLO'
'''
return decodedir(_decodefname(s))
def _buildlowerencodefun():
'''
>>> f = _buildlowerencodefun()
>>> f(b'nothing/special.txt')
'nothing/special.txt'
>>> f(b'HELLO')
'hello'
>>> f(b'hello:world?')
'hello~3aworld~3f'
>>> f(b'the\\x07quick\\xADshot')
'the~07quick~adshot'
'''
xchr = pycompat.bytechr
cmap = dict([(xchr(x), xchr(x)) for x in pycompat.xrange(127)])
for x in _reserved():
cmap[xchr(x)] = "~%02x" % x
for x in range(ord("A"), ord("Z") + 1):
cmap[xchr(x)] = xchr(x).lower()
def lowerencode(s):
return "".join([cmap[c] for c in pycompat.iterbytestr(s)])
return lowerencode
lowerencode = getattr(parsers, 'lowerencode', None) or _buildlowerencodefun()
# Windows reserved names: con, prn, aux, nul, com1..com9, lpt1..lpt9
_winres3 = ('aux', 'con', 'prn', 'nul') # length 3
_winres4 = ('com', 'lpt') # length 4 (with trailing 1..9)
def _auxencode(path, dotencode):
'''
Encodes filenames containing names reserved by Windows or which end in
period or space. Does not touch other single reserved characters c.
Specifically, c in '\\:*?"<>|' or ord(c) <= 31 are *not* encoded here.
Additionally encodes space or period at the beginning, if dotencode is
True. Parameter path is assumed to be all lowercase.
A segment only needs encoding if a reserved name appears as a
basename (e.g. "aux", "aux.foo"). A directory or file named "foo.aux"
doesn't need encoding.
>>> s = b'.foo/aux.txt/txt.aux/con/prn/nul/foo.'
>>> _auxencode(s.split(b'/'), True)
['~2efoo', 'au~78.txt', 'txt.aux', 'co~6e', 'pr~6e', 'nu~6c', 'foo~2e']
>>> s = b'.com1com2/lpt9.lpt4.lpt1/conprn/com0/lpt0/foo.'
>>> _auxencode(s.split(b'/'), False)
['.com1com2', 'lp~749.lpt4.lpt1', 'conprn', 'com0', 'lpt0', 'foo~2e']
>>> _auxencode([b'foo. '], True)
['foo.~20']
>>> _auxencode([b' .foo'], True)
['~20.foo']
'''
for i, n in enumerate(path):
if not n:
continue
if dotencode and n[0] in '. ':
n = "~%02x" % ord(n[0:1]) + n[1:]
path[i] = n
else:
l = n.find('.')
if l == -1:
l = len(n)
if ((l == 3 and n[:3] in _winres3) or
(l == 4 and n[3:4] <= '9' and n[3:4] >= '1'
and n[:3] in _winres4)):
# encode third letter ('aux' -> 'au~78')
ec = "~%02x" % ord(n[2:3])
n = n[0:2] + ec + n[3:]
path[i] = n
if n[-1] in '. ':
# encode last period or space ('foo...' -> 'foo..~2e')
path[i] = n[:-1] + "~%02x" % ord(n[-1:])
return path
_maxstorepathlen = 120
_dirprefixlen = 8
_maxshortdirslen = 8 * (_dirprefixlen + 1) - 4
def _hashencode(path, dotencode):
digest = node.hex(hashlib.sha1(path).digest())
le = lowerencode(path[5:]).split('/') # skips prefix 'data/' or 'meta/'
parts = _auxencode(le, dotencode)
basename = parts[-1]
_root, ext = os.path.splitext(basename)
sdirs = []
sdirslen = 0
for p in parts[:-1]:
d = p[:_dirprefixlen]
if d[-1] in '. ':
# Windows can't access dirs ending in period or space
d = d[:-1] + '_'
if sdirslen == 0:
t = len(d)
else:
t = sdirslen + 1 + len(d)
if t > _maxshortdirslen:
break
sdirs.append(d)
sdirslen = t
dirs = '/'.join(sdirs)
if len(dirs) > 0:
dirs += '/'
res = 'dh/' + dirs + digest + ext
spaceleft = _maxstorepathlen - len(res)
if spaceleft > 0:
filler = basename[:spaceleft]
res = 'dh/' + dirs + filler + digest + ext
return res
def _hybridencode(path, dotencode):
'''encodes path with a length limit
Encodes all paths that begin with 'data/', according to the following.
Default encoding (reversible):
Encodes all uppercase letters 'X' as '_x'. All reserved or illegal
characters are encoded as '~xx', where xx is the two digit hex code
of the character (see encodefilename).
Relevant path components consisting of Windows reserved filenames are
masked by encoding the third character ('aux' -> 'au~78', see _auxencode).
Hashed encoding (not reversible):
If the default-encoded path is longer than _maxstorepathlen, a
non-reversible hybrid hashing of the path is done instead.
This encoding uses up to _dirprefixlen characters of all directory
levels of the lowerencoded path, but not more levels than can fit into
_maxshortdirslen.
Then follows the filler followed by the sha digest of the full path.
The filler is the beginning of the basename of the lowerencoded path
(the basename is everything after the last path separator). The filler
is as long as possible, filling in characters from the basename until
the encoded path has _maxstorepathlen characters (or all chars of the
basename have been taken).
The extension (e.g. '.i' or '.d') is preserved.
The string 'data/' at the beginning is replaced with 'dh/', if the hashed
encoding was used.
'''
path = encodedir(path)
ef = _encodefname(path).split('/')
res = '/'.join(_auxencode(ef, dotencode))
if len(res) > _maxstorepathlen:
res = _hashencode(path, dotencode)
return res
def _pathencode(path):
de = encodedir(path)
if len(path) > _maxstorepathlen:
return _hashencode(de, True)
ef = _encodefname(de).split('/')
res = '/'.join(_auxencode(ef, True))
if len(res) > _maxstorepathlen:
return _hashencode(de, True)
return res
_pathencode = getattr(parsers, 'pathencode', _pathencode)
def _plainhybridencode(f):
return _hybridencode(f, False)
def _calcmode(vfs):
try:
# files in .hg/ will be created using this mode
mode = vfs.stat().st_mode
# avoid some useless chmods
if (0o777 & ~util.umask) == (0o777 & mode):
mode = None
except OSError:
mode = None
return mode
_data = ('narrowspec data meta 00manifest.d 00manifest.i'
' 00changelog.d 00changelog.i phaseroots obsstore')
def isrevlog(f, kind, st):
return kind == stat.S_IFREG and f[-2:] in ('.i', '.d')
class basicstore(object):
'''base class for local repository stores'''
def __init__(self, path, vfstype):
vfs = vfstype(path)
self.path = vfs.base
self.createmode = _calcmode(vfs)
vfs.createmode = self.createmode
self.rawvfs = vfs
self.vfs = vfsmod.filtervfs(vfs, encodedir)
self.opener = self.vfs
def join(self, f):
return self.path + '/' + encodedir(f)
def _walk(self, relpath, recurse, filefilter=isrevlog):
'''yields (unencoded, encoded, size)'''
path = self.path
if relpath:
path += '/' + relpath
striplen = len(self.path) + 1
l = []
if self.rawvfs.isdir(path):
visit = [path]
readdir = self.rawvfs.readdir
while visit:
p = visit.pop()
for f, kind, st in readdir(p, stat=True):
fp = p + '/' + f
if filefilter(f, kind, st):
n = util.pconvert(fp[striplen:])
l.append((decodedir(n), n, st.st_size))
elif kind == stat.S_IFDIR and recurse:
visit.append(fp)
l.sort()
return l
def datafiles(self):
return self._walk('data', True) + self._walk('meta', True)
def topfiles(self):
# yield manifest before changelog
return reversed(self._walk('', False))
def walk(self):
'''yields (unencoded, encoded, size)'''
# yield data files first
for x in self.datafiles():
yield x
for x in self.topfiles():
yield x
def copylist(self):
return ['requires'] + _data.split()
def write(self, tr):
pass
def invalidatecaches(self):
pass
def markremoved(self, fn):
pass
def __contains__(self, path):
'''Checks if the store contains path'''
path = "/".join(("data", path))
# file?
if self.vfs.exists(path + ".i"):
return True
# dir?
if not path.endswith("/"):
path = path + "/"
return self.vfs.exists(path)
class encodedstore(basicstore):
def __init__(self, path, vfstype):
vfs = vfstype(path + '/store')
self.path = vfs.base
self.createmode = _calcmode(vfs)
vfs.createmode = self.createmode
self.rawvfs = vfs
self.vfs = vfsmod.filtervfs(vfs, encodefilename)
self.opener = self.vfs
def datafiles(self):
for a, b, size in super(encodedstore, self).datafiles():
try:
a = decodefilename(a)
except KeyError:
a = None
yield a, b, size
def join(self, f):
return self.path + '/' + encodefilename(f)
def copylist(self):
return (['requires', '00changelog.i'] +
['store/' + f for f in _data.split()])
class fncache(object):
# the filename used to be partially encoded
# hence the encodedir/decodedir dance
def __init__(self, vfs):
self.vfs = vfs
self.entries = None
self._dirty = False
def _load(self):
'''fill the entries from the fncache file'''
self._dirty = False
try:
fp = self.vfs('fncache', mode='rb')
except IOError:
# skip nonexistent file
self.entries = set()
return
self.entries = set(decodedir(fp.read()).splitlines())
if '' in self.entries:
fp.seek(0)
for n, line in enumerate(util.iterfile(fp)):
if not line.rstrip('\n'):
t = _('invalid entry in fncache, line %d') % (n + 1)
raise error.Abort(t)
fp.close()
def write(self, tr):
if self._dirty:
assert self.entries is not None
tr.addbackup('fncache')
fp = self.vfs('fncache', mode='wb', atomictemp=True)
if self.entries:
fp.write(encodedir('\n'.join(self.entries) + '\n'))
fp.close()
self._dirty = False
def add(self, fn):
if self.entries is None:
self._load()
if fn not in self.entries:
self._dirty = True
self.entries.add(fn)
def remove(self, fn):
if self.entries is None:
self._load()
try:
self.entries.remove(fn)
self._dirty = True
except KeyError:
pass
def __contains__(self, fn):
if self.entries is None:
self._load()
return fn in self.entries
def __iter__(self):
if self.entries is None:
self._load()
return iter(self.entries)
class _fncachevfs(vfsmod.abstractvfs, vfsmod.proxyvfs):
def __init__(self, vfs, fnc, encode):
vfsmod.proxyvfs.__init__(self, vfs)
self.fncache = fnc
self.encode = encode
def __call__(self, path, mode='r', *args, **kw):
encoded = self.encode(path)
if mode not in ('r', 'rb') and (path.startswith('data/') or
path.startswith('meta/')):
# do not trigger a fncache load when adding a file that already is
# known to exist.
notload = self.fncache.entries is None and self.vfs.exists(encoded)
if notload and 'a' in mode and not self.vfs.stat(encoded).st_size:
# when appending to an existing file, if the file has size zero,
# it should be considered as missing. Such zero-size files are
# the result of truncation when a transaction is aborted.
notload = False
if not notload:
self.fncache.add(path)
return self.vfs(encoded, mode, *args, **kw)
def join(self, path):
if path:
return self.vfs.join(self.encode(path))
else:
return self.vfs.join(path)
class fncachestore(basicstore):
def __init__(self, path, vfstype, dotencode):
if dotencode:
encode = _pathencode
else:
encode = _plainhybridencode
self.encode = encode
vfs = vfstype(path + '/store')
self.path = vfs.base
self.pathsep = self.path + '/'
self.createmode = _calcmode(vfs)
vfs.createmode = self.createmode
self.rawvfs = vfs
fnc = fncache(vfs)
self.fncache = fnc
self.vfs = _fncachevfs(vfs, fnc, encode)
self.opener = self.vfs
def join(self, f):
return self.pathsep + self.encode(f)
def getsize(self, path):
return self.rawvfs.stat(path).st_size
def datafiles(self):
for f in sorted(self.fncache):
ef = self.encode(f)
try:
yield f, ef, self.getsize(ef)
except OSError as err:
if err.errno != errno.ENOENT:
raise
def copylist(self):
d = ('narrowspec data meta dh fncache phaseroots obsstore'
' 00manifest.d 00manifest.i 00changelog.d 00changelog.i')
return (['requires', '00changelog.i'] +
['store/' + f for f in d.split()])
def write(self, tr):
self.fncache.write(tr)
def invalidatecaches(self):
self.fncache.entries = None
def markremoved(self, fn):
self.fncache.remove(fn)
def _exists(self, f):
ef = self.encode(f)
try:
self.getsize(ef)
return True
except OSError as err:
if err.errno != errno.ENOENT:
raise
# nonexistent entry
return False
def __contains__(self, path):
'''Checks if the store contains path'''
path = "/".join(("data", path))
# check for files (exact match)
e = path + '.i'
if e in self.fncache and self._exists(e):
return True
# now check for directories (prefix match)
if not path.endswith('/'):
path += '/'
for e in self.fncache:
if e.startswith(path) and self._exists(e):
return True
return False
def store(requirements, path, vfstype):
if 'store' in requirements:
if 'fncache' in requirements:
return fncachestore(path, vfstype, 'dotencode' in requirements)
return encodedstore(path, vfstype)
return basicstore(path, vfstype)