Mercurial > hg
view tests/test-rust-ancestor.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 | 8a8305f557d0 |
children | 59fa3890d40a |
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from __future__ import absolute_import import sys import unittest from mercurial import ( error, node, ) from mercurial.testing import revlog as revlogtesting try: from mercurial import rustext rustext.__name__ # trigger immediate actual import except ImportError: rustext = None else: # this would fail already without appropriate ancestor.__package__ from mercurial.rustext.ancestor import ( AncestorsIterator, LazyAncestors, MissingAncestors, ) from mercurial.rustext import dagop try: from mercurial.cext import parsers as cparsers except ImportError: cparsers = None @unittest.skipIf( rustext is None, 'The Rust version of the "ancestor" module is not available. It is needed' ' for this test.', ) @unittest.skipIf( rustext is None, 'The Rust or C version of the "parsers" module, which the "ancestor" module' ' relies on, is not available.', ) class rustancestorstest(revlogtesting.RevlogBasedTestBase): """Test the correctness of binding to Rust code. This test is merely for the binding to Rust itself: extraction of Python variable, giving back the results etc. It is not meant to test the algorithmic correctness of the operations on ancestors it provides. Hence the very simple embedded index data is good enough. Algorithmic correctness is asserted by the Rust unit tests. """ def testiteratorrevlist(self): idx = self.parseindex() # checking test assumption about the index binary data: self.assertEqual( {i: (r[5], r[6]) for i, r in enumerate(idx)}, {0: (-1, -1), 1: (0, -1), 2: (1, -1), 3: (2, -1)}, ) ait = AncestorsIterator(idx, [3], 0, True) self.assertEqual([r for r in ait], [3, 2, 1, 0]) ait = AncestorsIterator(idx, [3], 0, False) self.assertEqual([r for r in ait], [2, 1, 0]) def testlazyancestors(self): idx = self.parseindex() start_count = sys.getrefcount(idx) # should be 2 (see Python doc) self.assertEqual( {i: (r[5], r[6]) for i, r in enumerate(idx)}, {0: (-1, -1), 1: (0, -1), 2: (1, -1), 3: (2, -1)}, ) lazy = LazyAncestors(idx, [3], 0, True) # we have two more references to the index: # - in its inner iterator for __contains__ and __bool__ # - in the LazyAncestors instance itself (to spawn new iterators) self.assertEqual(sys.getrefcount(idx), start_count + 2) self.assertTrue(2 in lazy) self.assertTrue(bool(lazy)) self.assertEqual(list(lazy), [3, 2, 1, 0]) # a second time to validate that we spawn new iterators self.assertEqual(list(lazy), [3, 2, 1, 0]) # now let's watch the refcounts closer ait = iter(lazy) self.assertEqual(sys.getrefcount(idx), start_count + 3) del ait self.assertEqual(sys.getrefcount(idx), start_count + 2) del lazy self.assertEqual(sys.getrefcount(idx), start_count) # let's check bool for an empty one self.assertFalse(LazyAncestors(idx, [0], 0, False)) def testmissingancestors(self): idx = self.parseindex() missanc = MissingAncestors(idx, [1]) self.assertTrue(missanc.hasbases()) self.assertEqual(missanc.missingancestors([3]), [2, 3]) missanc.addbases({2}) self.assertEqual(missanc.bases(), {1, 2}) self.assertEqual(missanc.missingancestors([3]), [3]) self.assertEqual(missanc.basesheads(), {2}) def testmissingancestorsremove(self): idx = self.parseindex() missanc = MissingAncestors(idx, [1]) revs = {0, 1, 2, 3} missanc.removeancestorsfrom(revs) self.assertEqual(revs, {2, 3}) def testrefcount(self): idx = self.parseindex() start_count = sys.getrefcount(idx) # refcount increases upon iterator init... ait = AncestorsIterator(idx, [3], 0, True) self.assertEqual(sys.getrefcount(idx), start_count + 1) self.assertEqual(next(ait), 3) # and decreases once the iterator is removed del ait self.assertEqual(sys.getrefcount(idx), start_count) # and removing ref to the index after iterator init is no issue ait = AncestorsIterator(idx, [3], 0, True) del idx self.assertEqual(list(ait), [3, 2, 1, 0]) def testgrapherror(self): data = ( revlogtesting.data_non_inlined[: 64 + 27] + b'\xf2' + revlogtesting.data_non_inlined[64 + 28 :] ) idx = cparsers.parse_index2(data, False)[0] with self.assertRaises(rustext.GraphError) as arc: AncestorsIterator(idx, [1], -1, False) exc = arc.exception self.assertIsInstance(exc, ValueError) # rust-cpython issues appropriate str instances for Python 2 and 3 self.assertEqual(exc.args, ('ParentOutOfRange', 1)) def testwdirunsupported(self): # trying to access ancestors of the working directory raises # WdirUnsupported directly idx = self.parseindex() with self.assertRaises(error.WdirUnsupported): list(AncestorsIterator(idx, [node.wdirrev], -1, False)) def testheadrevs(self): idx = self.parseindex() self.assertEqual(dagop.headrevs(idx, [1, 2, 3]), {3}) if __name__ == '__main__': import silenttestrunner silenttestrunner.main(__name__)