[PATCH v2] lazymanifest: write a more efficient, pypy friendly version of lazymanifest
Maciej Fijalkowski
fijall at gmail.com
Sun Sep 25 07:13:29 UTC 2016
I must say (and you are going to say that those are idle complaints)
that asserts and prints are far inferior than a proper debugger which
is surprisingly hard to use in the case of mercurial tests
On Tue, Sep 20, 2016 at 4:39 PM, Augie Fackler <raf at durin42.com> wrote:
> On Sat, Sep 17, 2016 at 08:23:36PM +0200, Maciej Fijalkowski wrote:
>> This should fix the issues presented.
>>
>> There is one problem which is that the hash in test-rebase-detach
>> changes. The way I see it is just an RNG phase-shift, but it might be
>> a real bug. Some actual input will be appreciated.
>
> It's not possibly RNG related - there's no RNG that goes into the sha1
> of a node. I've added --debug to the failure in test-rebase-detach and
> compared them between cpython and pypy:
>
> cpython:
> @@ -366,11 +366,24 @@
>
>
> $ hg log --rev tip --debug
> - changeset: 8:9472f4b1d736
> + changeset: 8:9472f4b1d7366902d0098aa1401e3f170000cc56
> tag: tip
> + phase: draft
> + parent: 7:02de42196ebee42ef284b6780a87cdc96e8eaab6
> + parent: -1:0000000000000000000000000000000000000000
> + manifest: 8:8dbdcf066a97239fde2d0dba19fcb1e699fa66d2
> user: test
> date: Thu Jan 01 00:00:00 1970 +0000
> - summary: Collapsed revision
> + files: F
> + files+: E
> + extra: branch=default
> + extra: rebase_source=9427d4d5af81c393e6b630129712cde8cdad5605
> + description:
> + Collapsed revision
> + * I
> + * Merge
> + * J
> +
>
>
> pypy:
> @@ -366,11 +366,24 @@
>
>
> $ hg log --rev tip --debug
> - changeset: 8:9472f4b1d736
> + changeset: 8:122ceff3b303b13e5ca323742a8ebe589b9f8066
> tag: tip
> + phase: draft
> + parent: 7:02de42196ebee42ef284b6780a87cdc96e8eaab6
> + parent: -1:0000000000000000000000000000000000000000
> + manifest: 8:09f1dc369d2667dcaeb9cf828b0fcb76bda29f33
> user: test
> date: Thu Jan 01 00:00:00 1970 +0000
> - summary: Collapsed revision
> + files: F
> + files+: E
> + extra: branch=default
> + extra: rebase_source=9427d4d5af81c393e6b630129712cde8cdad5605
> + description:
> + Collapsed revision
> + * I
> + * Merge
> + * J
> +
>
> Which means the manifest is hashing out differently. That suggests
> there's a subtle bug in how the manifest is hashing out in the pypy
> version. Adding a `hg debugdata -m 8` (which prints raw manifest
> data), and this is what I get on cpython:
>
> $ hg debugdata -m 8
> + A\x0045f17b21388f07b8939b22052e5f3776e5246388 (esc)
> + E\x00c3b9643004a8d1c7f39b0025cefab53dc8f7dc12 (esc)
> + F\x00293a00dc38ac20f042c67ba8534eedc1b6a7ae15 (esc)
> + H\x008500189e74a9e0475e822093bc7db0d631aeb0b4 (esc)
>
> on pypy:
> $ hg debugdata -m 8
> + A\x0045f17b21388f07b8939b22052e5f3776e5246388 (esc)
> + F\x0022bfcfd62a21a3287edbd4d656218d0f525ed76a (esc)
> + E\x00c3b9643004a8d1c7f39b0025cefab53dc8f7dc12 (esc)
> + F\x00293a00dc38ac20f042c67ba8534eedc1b6a7ae15 (esc)
> + H\x008500189e74a9e0475e822093bc7db0d631aeb0b4 (esc)
>
>
> So you've got a subtle bug here where the compaction of the
> lazymanifest isn't working right - probably around merging manifests
> somehow. Does this give you enough to get started?
>
> (I'd probably start debugging this by littering _lazymanifest._compact
> and _lazymanifest.text with asserts until I managed to trip over the
> un-sorted lines, and then backtrack from there to figure out how they
> managed to survive.)
>
>>
>>
>>
>> On Sat, Sep 17, 2016 at 8:22 PM, Maciej Fijalkowski <fijall at gmail.com> wrote:
>> > # HG changeset patch
>> > # User Maciej Fijalkowski <fijall at gmail.com>
>> > # Date 1473680234 -7200
>> > # Mon Sep 12 13:37:14 2016 +0200
>> > # Node ID 7551f1e60b2155462d89a9571eec065e9f67debc
>> > # Parent df05c43bd1e64f1620d0b2e502f4603c1e5a8341
>> > lazymanifest: write a more efficient, pypy friendly version of lazymanifest
>> >
>> > diff --git a/mercurial/manifest.py b/mercurial/manifest.py
>> > --- a/mercurial/manifest.py
>> > +++ b/mercurial/manifest.py
>> > @@ -104,69 +104,297 @@
>> > _checkforbidden(files)
>> > return ''.join(lines)
>> >
>> > -class _lazymanifest(dict):
>> > - """This is the pure implementation of lazymanifest.
>> > -
>> > - It has not been optimized *at all* and is not lazy.
>> > - """
>> > -
>> > - def __init__(self, data):
>> > - dict.__init__(self)
>> > - for f, n, fl in _parse(data):
>> > - self[f] = n, fl
>> > -
>> > - def __setitem__(self, k, v):
>> > - node, flag = v
>> > - assert node is not None
>> > - if len(node) > 21:
>> > - node = node[:21] # match c implementation behavior
>> > - dict.__setitem__(self, k, (node, flag))
>> > +class lazymanifestiter(object):
>> > + def __init__(self, lm):
>> > + self.pos = 0
>> > + self.lm = lm
>> >
>> > def __iter__(self):
>> > - return iter(sorted(dict.keys(self)))
>> > + return self
>> >
>> > - def iterkeys(self):
>> > - return iter(sorted(dict.keys(self)))
>> > + def next(self):
>> > + try:
>> > + data, pos = self.lm._get(self.pos)
>> > + except IndexError:
>> > + raise StopIteration
>> > + if pos == -1:
>> > + self.pos += 1
>> > + return data[0]
>> > + self.pos += 1
>> > + zeropos = data.find('\x00', pos)
>> > + return data[pos:zeropos]
>> >
>> > - def iterentries(self):
>> > - return ((f, e[0], e[1]) for f, e in sorted(self.iteritems()))
>> > +class lazymanifestiterentries(object):
>> > + def __init__(self, lm):
>> > + self.lm = lm
>> > + self.pos = 0
>> > +
>> > + def __iter__(self):
>> > + return self
>> > +
>> > + def next(self):
>> > + try:
>> > + data, pos = self.lm._get(self.pos)
>> > + except IndexError:
>> > + raise StopIteration
>> > + if pos == -1:
>> > + self.pos += 1
>> > + return data
>> > + zeropos = data.find('\x00', pos)
>> > + hashval = unhexlify(data, self.lm.extrainfo[self.pos],
>> > + zeropos + 1, 40)
>> > + flags = self.lm._getflags(data, self.pos, zeropos)
>> > + self.pos += 1
>> > + return (data[pos:zeropos], hashval, flags)
>> > +
>> > +def unhexlify(data, extra, pos, length):
>> > + s = data[pos:pos + length].decode('hex')
>> > + if extra:
>> > + s += chr(extra & 0xff)
>> > + return s
>> > +
>> > +def _cmp(a, b):
>> > + return (a > b) - (a < b)
>> > +
>> > +class _lazymanifest(object):
>> > + def __init__(self, data, positions=None, extrainfo=None, extradata=None):
>> > + if positions is None:
>> > + self.positions = self.findlines(data)
>> > + self.extrainfo = [0] * len(self.positions)
>> > + self.data = data
>> > + self.extradata = []
>> > + else:
>> > + self.positions = positions[:]
>> > + self.extrainfo = extrainfo[:]
>> > + self.extradata = extradata[:]
>> > + self.data = data
>> > +
>> > + def findlines(self, data):
>> > + if not data:
>> > + return []
>> > + pos = data.find("\n")
>> > + positions = [0]
>> > + while pos < len(data) - 1 and pos != -1:
>> > + positions.append(pos + 1)
>> > + pos = data.find("\n", pos + 1)
>> > + return positions
>> > +
>> > + def _get(self, index):
>> > + # get the position encoded in pos:
>> > + # positive number is an index in 'data'
>> > + # negative number is in extrapieces
>> > + pos = self.positions[index]
>> > + if pos >= 0:
>> > + return self.data, pos
>> > + return self.extradata[-pos - 1], -1
>> > +
>> > + def _getkey(self, pos):
>> > + if pos >= 0:
>> > + return self.data[pos:self.data.find('\x00', pos + 1)]
>> > + return self.extradata[-pos - 1][0]
>> > +
>> > + def bsearch(self, key):
>> > + first = 0
>> > + last = len(self.positions) - 1
>> > +
>> > + while first <= last:
>> > + midpoint = (first + last)//2
>> > + nextpos = self.positions[midpoint]
>> > + candidate = self._getkey(nextpos)
>> > + r = _cmp(key, candidate)
>> > + if r == 0:
>> > + return midpoint
>> > + else:
>> > + if r < 0:
>> > + last = midpoint - 1
>> > + else:
>> > + first = midpoint + 1
>> > + return -1
>> > +
>> > + def bsearch2(self, key):
>> > + # same as the above, but will always return the position
>> > + # done for performance reasons
>> > + first = 0
>> > + last = len(self.positions) - 1
>> > +
>> > + while first <= last:
>> > + midpoint = (first + last)//2
>> > + nextpos = self.positions[midpoint]
>> > + candidate = self._getkey(nextpos)
>> > + r = _cmp(key, candidate)
>> > + if r == 0:
>> > + return (midpoint, True)
>> > + else:
>> > + if r < 0:
>> > + last = midpoint - 1
>> > + else:
>> > + first = midpoint + 1
>> > + return (first, False)
>> > +
>> > + def __contains__(self, key):
>> > + return self.bsearch(key) != -1
>> > +
>> > + def _getflags(self, data, needle, pos):
>> > + start = pos + 41
>> > + end = data.find("\n", start)
>> > + if end == -1:
>> > + end = len(data) - 1
>> > + if start == end:
>> > + return ''
>> > + return self.data[start:end]
>> > +
>> > + def __getitem__(self, key):
>> > + if not isinstance(key, str):
>> > + raise TypeError("getitem: manifest keys must be a string.")
>> > + needle = self.bsearch(key)
>> > + if needle == -1:
>> > + raise KeyError
>> > + data, pos = self._get(needle)
>> > + if pos == -1:
>> > + return (data[1], data[2])
>> > + zeropos = data.find('\x00', pos)
>> > + assert 0 <= needle <= len(self.positions)
>> > + assert len(self.extrainfo) == len(self.positions)
>> > + hashval = unhexlify(data, self.extrainfo[needle], zeropos + 1, 40)
>> > + flags = self._getflags(data, needle, zeropos)
>> > + return (hashval, flags)
>> > +
>> > + def __delitem__(self, key):
>> > + needle, found = self.bsearch2(key)
>> > + if not found:
>> > + raise KeyError
>> > + cur = self.positions[needle]
>> > + self.positions = self.positions[:needle] + self.positions[needle + 1:]
>> > + self.extrainfo = self.extrainfo[:needle] + self.extrainfo[needle + 1:]
>> > + if cur >= 0:
>> > + self.data = self.data[:cur] + '\x00' + self.data[cur + 1:]
>> > +
>> > + def __setitem__(self, key, value):
>> > + if not isinstance(key, str):
>> > + raise TypeError("setitem: manifest keys must be a string.")
>> > + if not isinstance(value, tuple) or len(value) != 2:
>> > + raise TypeError("Manifest values must be a tuple of (node, flags).")
>> > + hashval = value[0]
>> > + if not isinstance(hashval, str) or not 20 <= len(hashval) <= 22:
>> > + raise TypeError("node must be a 20-byte string")
>> > + flags = value[1]
>> > + if not isinstance(flags, str) or len(flags) > 1:
>> > + raise TypeError("flags must a 0 or 1 byte string, got %r", flags)
>> > + needle, found = self.bsearch2(key)
>> > + if found:
>> > + # put the item
>> > + pos = self.positions[needle]
>> > + if pos < 0:
>> > + self.extradata[-pos - 1] = (key, value[0], value[1])
>> > + else:
>> > + # just don't bother
>> > + self.extradata.append((key, value[0], value[1]))
>> > + self.positions[needle] = -len(self.extradata)
>> > + else:
>> > + # not found, put it in with extra positions
>> > + self.extradata.append((key, value[0], value[1]))
>> > + self.positions = (self.positions[:needle] + [-len(self.extradata)]
>> > + + self.positions[needle:])
>> > + self.extrainfo = (self.extrainfo[:needle] + [0] +
>> > + self.extrainfo[needle:])
>> >
>> > def copy(self):
>> > - c = _lazymanifest('')
>> > - c.update(self)
>> > - return c
>> > + # XXX call _compact like in C?
>> > + return _lazymanifest(self.data, self.positions, self.extrainfo,
>> > + self.extradata)
>> > +
>> > + def _compact(self):
>> > + # hopefully not called TOO often
>> > + def findnextposition(positions, start, lgt):
>> > + i = start
>> > + while i < len(positions):
>> > + if positions[i] >= 0:
>> > + return positions[i]
>> > + i += 1
>> > + return lgt
>> > +
>> > + if len(self.extradata) == 0:
>> > + return
>> > + l = []
>> > + last_cut = 0
>> > + i = 0
>> > + offset = 0
>> > + self.extrainfo = [0] * len(self.positions)
>> > + while i < len(self.positions):
>> > + if self.positions[i] >= 0:
>> > + cur = self.positions[i]
>> > + last_cut = cur
>> > + while True:
>> > + self.positions[i] = offset
>> > + i += 1
>> > + if i == len(self.positions) or self.positions[i] < 0:
>> > + break
>> > + offset += self.positions[i] - cur
>> > + cur = self.positions[i]
>> > + end_cut = findnextposition(self.positions, i, len(self.data))
>> > + offset += end_cut - cur
>> > + l.append(self.data[last_cut:end_cut])
>> > + else:
>> > + while i < len(self.positions) and self.positions[i] < 0:
>> > + cur = self.positions[i]
>> > + t = self.extradata[-cur - 1]
>> > + l.append(self._pack(t))
>> > + self.positions[i] = offset
>> > + if len(t[1]) > 20:
>> > + self.extrainfo[i] = ord(t[1][21])
>> > + offset += len(l[-1])
>> > + i += 1
>> > + self.data = ''.join(l)
>> > + self.extradata = []
>> > +
>> > + def _pack(self, d):
>> > + return d[0] + '\x00' + d[1][:20].encode('hex') + d[2] + '\n'
>> > +
>> > + def text(self):
>> > + self._compact()
>> > + return self.data
>> >
>> > def diff(self, m2, clean=False):
>> > '''Finds changes between the current manifest and m2.'''
>> > + # XXX think whether efficiency matters here
>> > diff = {}
>> >
>> > - for fn, e1 in self.iteritems():
>> > + for fn, e1, flags in self.iterentries():
>> > if fn not in m2:
>> > - diff[fn] = e1, (None, '')
>> > + diff[fn] = (e1, flags), (None, '')
>> > else:
>> > e2 = m2[fn]
>> > - if e1 != e2:
>> > - diff[fn] = e1, e2
>> > + if (e1, flags) != e2:
>> > + diff[fn] = (e1, flags), e2
>> > elif clean:
>> > diff[fn] = None
>> >
>> > - for fn, e2 in m2.iteritems():
>> > + for fn, e2, flags in m2.iterentries():
>> > if fn not in self:
>> > - diff[fn] = (None, ''), e2
>> > + diff[fn] = (None, ''), (e2, flags)
>> >
>> > return diff
>> >
>> > + def iterentries(self):
>> > + return lazymanifestiterentries(self)
>> > +
>> > + def iterkeys(self):
>> > + return lazymanifestiter(self)
>> > +
>> > + def __iter__(self):
>> > + return lazymanifestiter(self)
>> > +
>> > + def __len__(self):
>> > + return len(self.positions)
>> > +
>> > def filtercopy(self, filterfn):
>> > + # XXX should be optimized
>> > c = _lazymanifest('')
>> > for f, n, fl in self.iterentries():
>> > if filterfn(f):
>> > c[f] = n, fl
>> > return c
>> >
>> > - def text(self):
>> > - """Get the full data of this manifest as a bytestring."""
>> > - return _textv1(self.iterentries())
>> > -
>> > try:
>> > _lazymanifest = parsers.lazymanifest
>> > except AttributeError:
>> > diff --git a/mercurial/pure/bdiff.py b/mercurial/pure/bdiff.py
>> > --- a/mercurial/pure/bdiff.py
>> > +++ b/mercurial/pure/bdiff.py
>> > @@ -111,8 +111,8 @@
>> > def blocks(sa, sb):
>> > a = ffi.new("struct bdiff_line**")
>> > b = ffi.new("struct bdiff_line**")
>> > - ac = ffi.new("char[]", sa)
>> > - bc = ffi.new("char[]", sb)
>> > + ac = ffi.new("char[]", str(sa))
>> > + bc = ffi.new("char[]", str(sb))
>> > l = ffi.new("struct bdiff_hunk*")
>> > try:
>> > an = lib.bdiff_splitlines(ac, len(sa), a)
>> > @@ -138,8 +138,8 @@
>> > def bdiff(sa, sb):
>> > a = ffi.new("struct bdiff_line**")
>> > b = ffi.new("struct bdiff_line**")
>> > - ac = ffi.new("char[]", sa)
>> > - bc = ffi.new("char[]", sb)
>> > + ac = ffi.new("char[]", str(sa))
>> > + bc = ffi.new("char[]", str(sb))
>> > l = ffi.new("struct bdiff_hunk*")
>> > try:
>> > an = lib.bdiff_splitlines(ac, len(sa), a)
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