Mercurial > hg
view tests/test-lock.py @ 44363:f7459da77f23
nodemap: introduce an option to use mmap to read the nodemap mapping
The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.
This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).
Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:
Before:
* do not use the persistent nodemap
* use the CPython implementation of the index for nodemap
* use mmapping of the changelog index
After:
* use the MixedIndex Rust code, with the NodeTree object for nodemap access
(still in review)
* use the persistent nodemap data from disk
* access the persistent nodemap data through mmap
* use mmapping of the changelog index
The persistent nodemap greatly speed up most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.
Here are some numbers (in seconds) for the reference copy of mozilla-try:
Revset Before After abs-change speedup
-10000: 0.004622 0.005532 0.000910 × 0.83
-10: 0.000050 0.000132 0.000082 × 0.37
tip 0.000052 0.000085 0.000033 × 0.61
0 + (-10000:) 0.028222 0.005337 -0.022885 × 5.29
0 0.023521 0.000084 -0.023437 × 280.01
(-10000:) + 0 0.235539 0.005308 -0.230231 × 44.37
(-10:) + :9 0.232883 0.000180 -0.232703 ×1293.79
(-10000:) + (:99) 0.238735 0.005358 -0.233377 × 44.55
:99 + (-10000:) 0.317942 0.005593 -0.312349 × 56.84
:9 + (-10:) 0.313372 0.000179 -0.313193 ×1750.68
:9 0.316450 0.000143 -0.316307 ×2212.93
On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.
Here are some numbers (in seconds) for the reference copy of mercurial:
Revset Before After abs-change speedup
-10: 0.000065 0.000097 0.000032 × 0.67
tip 0.000063 0.000078 0.000015 × 0.80
0 0.000561 0.000079 -0.000482 × 7.10
-10000: 0.004609 0.003648 -0.000961 × 1.26
0 + (-10000:) 0.005023 0.003715 -0.001307 × 1.35
(-10:) + :9 0.002187 0.000108 -0.002079 ×20.25
(-10000:) + 0 0.006252 0.003716 -0.002536 × 1.68
(-10000:) + (:99) 0.006367 0.003707 -0.002660 × 1.71
:9 + (-10:) 0.003846 0.000110 -0.003736 ×34.96
:9 0.003854 0.000099 -0.003755 ×38.92
:99 + (-10000:) 0.007644 0.003778 -0.003866 × 2.02
Differential Revision: https://phab.mercurial-scm.org/D7894
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Tue, 11 Feb 2020 11:18:52 +0100 |
parents | 888bd39ed555 |
children | 9b16bb3b2349 |
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from __future__ import absolute_import import copy import errno import tempfile import types import unittest import silenttestrunner from mercurial import ( encoding, error, lock, vfs as vfsmod, ) testlockname = b'testlock' # work around http://bugs.python.org/issue1515 if types.MethodType not in copy._deepcopy_dispatch: def _deepcopy_method(x, memo): return type(x)(x.__func__, copy.deepcopy(x.__self__, memo), x.im_class) copy._deepcopy_dispatch[types.MethodType] = _deepcopy_method class lockwrapper(lock.lock): def __init__(self, pidoffset, *args, **kwargs): # lock.lock.__init__() calls lock(), so the pidoffset assignment needs # to be earlier self._pidoffset = pidoffset super(lockwrapper, self).__init__(*args, **kwargs) def _getpid(self): return super(lockwrapper, self)._getpid() + self._pidoffset class teststate(object): def __init__(self, testcase, dir, pidoffset=0): self._testcase = testcase self._acquirecalled = False self._releasecalled = False self._postreleasecalled = False self.vfs = vfsmod.vfs(dir, audit=False) self._pidoffset = pidoffset def makelock(self, *args, **kwargs): l = lockwrapper( self._pidoffset, self.vfs, testlockname, releasefn=self.releasefn, acquirefn=self.acquirefn, *args, **kwargs ) l.postrelease.append(self.postreleasefn) return l def acquirefn(self): self._acquirecalled = True def releasefn(self): self._releasecalled = True def postreleasefn(self, success): self._postreleasecalled = True def assertacquirecalled(self, called): self._testcase.assertEqual( self._acquirecalled, called, 'expected acquire to be %s but was actually %s' % (self._tocalled(called), self._tocalled(self._acquirecalled),), ) def resetacquirefn(self): self._acquirecalled = False def assertreleasecalled(self, called): self._testcase.assertEqual( self._releasecalled, called, 'expected release to be %s but was actually %s' % (self._tocalled(called), self._tocalled(self._releasecalled),), ) def assertpostreleasecalled(self, called): self._testcase.assertEqual( self._postreleasecalled, called, 'expected postrelease to be %s but was actually %s' % ( self._tocalled(called), self._tocalled(self._postreleasecalled), ), ) def assertlockexists(self, exists): actual = self.vfs.lexists(testlockname) self._testcase.assertEqual( actual, exists, 'expected lock to %s but actually did %s' % (self._toexists(exists), self._toexists(actual),), ) def _tocalled(self, called): if called: return 'called' else: return 'not called' def _toexists(self, exists): if exists: return 'exist' else: return 'not exist' class testlock(unittest.TestCase): def testlock(self): state = teststate(self, tempfile.mkdtemp(dir=encoding.getcwd())) lock = state.makelock() state.assertacquirecalled(True) lock.release() state.assertreleasecalled(True) state.assertpostreleasecalled(True) state.assertlockexists(False) def testrecursivelock(self): state = teststate(self, tempfile.mkdtemp(dir=encoding.getcwd())) lock = state.makelock() state.assertacquirecalled(True) state.resetacquirefn() lock.lock() # recursive lock should not call acquirefn again state.assertacquirecalled(False) lock.release() # brings lock refcount down from 2 to 1 state.assertreleasecalled(False) state.assertpostreleasecalled(False) state.assertlockexists(True) lock.release() # releases the lock state.assertreleasecalled(True) state.assertpostreleasecalled(True) state.assertlockexists(False) def testlockfork(self): state = teststate(self, tempfile.mkdtemp(dir=encoding.getcwd())) lock = state.makelock() state.assertacquirecalled(True) # fake a fork forklock = copy.copy(lock) forklock._pidoffset = 1 forklock.release() state.assertreleasecalled(False) state.assertpostreleasecalled(False) state.assertlockexists(True) # release the actual lock lock.release() state.assertreleasecalled(True) state.assertpostreleasecalled(True) state.assertlockexists(False) def testinheritlock(self): d = tempfile.mkdtemp(dir=encoding.getcwd()) parentstate = teststate(self, d) parentlock = parentstate.makelock() parentstate.assertacquirecalled(True) # set up lock inheritance with parentlock.inherit() as lockname: parentstate.assertreleasecalled(True) parentstate.assertpostreleasecalled(False) parentstate.assertlockexists(True) childstate = teststate(self, d, pidoffset=1) childlock = childstate.makelock(parentlock=lockname) childstate.assertacquirecalled(True) childlock.release() childstate.assertreleasecalled(True) childstate.assertpostreleasecalled(False) childstate.assertlockexists(True) parentstate.resetacquirefn() parentstate.assertacquirecalled(True) parentlock.release() parentstate.assertreleasecalled(True) parentstate.assertpostreleasecalled(True) parentstate.assertlockexists(False) def testmultilock(self): d = tempfile.mkdtemp(dir=encoding.getcwd()) state0 = teststate(self, d) lock0 = state0.makelock() state0.assertacquirecalled(True) with lock0.inherit() as lock0name: state0.assertreleasecalled(True) state0.assertpostreleasecalled(False) state0.assertlockexists(True) state1 = teststate(self, d, pidoffset=1) lock1 = state1.makelock(parentlock=lock0name) state1.assertacquirecalled(True) # from within lock1, acquire another lock with lock1.inherit() as lock1name: # since the file on disk is lock0's this should have the same # name self.assertEqual(lock0name, lock1name) state2 = teststate(self, d, pidoffset=2) lock2 = state2.makelock(parentlock=lock1name) state2.assertacquirecalled(True) lock2.release() state2.assertreleasecalled(True) state2.assertpostreleasecalled(False) state2.assertlockexists(True) state1.resetacquirefn() state1.assertacquirecalled(True) lock1.release() state1.assertreleasecalled(True) state1.assertpostreleasecalled(False) state1.assertlockexists(True) lock0.release() def testinheritlockfork(self): d = tempfile.mkdtemp(dir=encoding.getcwd()) parentstate = teststate(self, d) parentlock = parentstate.makelock() parentstate.assertacquirecalled(True) # set up lock inheritance with parentlock.inherit() as lockname: childstate = teststate(self, d, pidoffset=1) childlock = childstate.makelock(parentlock=lockname) childstate.assertacquirecalled(True) # fork the child lock forkchildlock = copy.copy(childlock) forkchildlock._pidoffset += 1 forkchildlock.release() childstate.assertreleasecalled(False) childstate.assertpostreleasecalled(False) childstate.assertlockexists(True) # release the child lock childlock.release() childstate.assertreleasecalled(True) childstate.assertpostreleasecalled(False) childstate.assertlockexists(True) parentlock.release() def testinheritcheck(self): d = tempfile.mkdtemp(dir=encoding.getcwd()) state = teststate(self, d) def check(): raise error.LockInheritanceContractViolation('check failed') lock = state.makelock(inheritchecker=check) state.assertacquirecalled(True) with self.assertRaises(error.LockInheritanceContractViolation): with lock.inherit(): pass lock.release() def testfrequentlockunlock(self): """This tests whether lock acquisition fails as expected, even if (1) lock can't be acquired (makelock fails by EEXIST), and (2) locker info can't be read in (readlock fails by ENOENT) while retrying 5 times. """ d = tempfile.mkdtemp(dir=encoding.getcwd()) state = teststate(self, d) def emulatefrequentlock(*args): raise OSError(errno.EEXIST, "File exists") def emulatefrequentunlock(*args): raise OSError(errno.ENOENT, "No such file or directory") state.vfs.makelock = emulatefrequentlock state.vfs.readlock = emulatefrequentunlock try: state.makelock(timeout=0) self.fail("unexpected lock acquisition") except error.LockHeld as why: self.assertTrue(why.errno == errno.ETIMEDOUT) self.assertTrue(why.locker == b"") state.assertlockexists(False) if __name__ == '__main__': silenttestrunner.main(__name__)