setdiscovery: stop limiting the number of local head we initially send
In our testing this limitation provides now real gain and instead triggers
pathological discovery timing for some repository with many heads.
See inline documentation for details.
Some timing below:
Mozilla try repository, (~1M revs, ~35K heads), discovery between 2 clones with
100 head missing on each side
before:
! wall 1.492111 comb 1.490000 user 1.450000 sys 0.040000 (best of 20)
! wall 1.813992 comb 1.820000 user 1.700000 sys 0.120000 (max of 20)
! wall 1.574326 comb 1.573500 user 1.522000 sys 0.051500 (avg of 20)
! wall 1.572583 comb 1.570000 user 1.520000 sys 0.050000 (median of 20)
after:
! wall 1.147834 comb 1.150000 user 1.090000 sys 0.060000 (best of 20)
! wall 1.449144 comb 1.450000 user 1.330000 sys 0.120000 (max of 20)
! wall 1.204618 comb 1.202500 user 1.146500 sys 0.056000 (avg of 20)
! wall 1.194407 comb 1.190000 user 1.140000 sys 0.050000 (median of 20)
pypy (~100 heads, 317 heads) discovery between clones with only 42 common heads
before:
! wall 0.031653 comb 0.030000 user 0.030000 sys 0.000000 (best of 25)
! wall 0.055719 comb 0.050000 user 0.040000 sys 0.010000 (max of 25)
! wall 0.038939 comb 0.039600 user 0.038400 sys 0.001200 (avg of 25)
! wall 0.038660 comb 0.050000 user 0.040000 sys 0.010000 (median of 25)
after:
! wall 0.018754 comb 0.020000 user 0.020000 sys 0.000000 (best of 49)
! wall 0.034505 comb 0.040000 user 0.030000 sys 0.010000 (max of 49)
! wall 0.019631 comb 0.019796 user 0.018367 sys 0.001429 (avg of 49)
! wall 0.019132 comb 0.020000 user 0.020000 sys 0.000000 (median of 49)
Private repository (~1M revs, ~3K heads), discovery from a strip subset, about
100 changesets to be pulled.
before:
! wall 1.837729 comb 1.840000 user 1.790000 sys 0.050000 (best of 20)
! wall 2.203468 comb 2.200000 user 2.100000 sys 0.100000 (max of 20)
! wall 2.049355 comb 2.048500 user 2.002500 sys 0.046000 (avg of 20)
! wall 2.035315 comb 2.040000 user 2.000000 sys 0.040000 (median of 20)
after:
! wall 0.136598 comb 0.130000 user 0.110000 sys 0.020000 (best of 20)
! wall 0.330519 comb 0.330000 user 0.260000 sys 0.070000 (max of 20)
! wall 0.157254 comb 0.155500 user 0.123000 sys 0.032500 (avg of 20)
! wall 0.149870 comb 0.140000 user 0.110000 sys 0.030000 (median of 20)
Same private repo, discovery between two clone with 500 different heads on each
side:
before:
! wall 2.372919 comb 2.370000 user 2.320000 sys 0.050000 (best of 20)
! wall 2.622422 comb 2.610000 user 2.510000 sys 0.100000 (max of 20)
! wall 2.450135 comb 2.450000 user 2.402000 sys 0.048000 (avg of 20)
! wall 2.443896 comb 2.450000 user 2.410000 sys 0.040000 (median of 20)
after:
! wall 0.625497 comb 0.620000 user 0.570000 sys 0.050000 (best of 20)
! wall 0.834723 comb 0.820000 user 0.730000 sys 0.090000 (max of 20)
! wall 0.675725 comb 0.675500 user 0.628000 sys 0.047500 (avg of 20)
! wall 0.671614 comb 0.680000 user 0.640000 sys 0.040000 (median of 20)
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):
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__)