view tests/test-rust-discovery.py @ 51108:0250e45040f1

revlog: add a small cache of unfiltered chunk

This can provides a massive boost to the reading of multiple revision and the
computation of a valid delta chain.

This greatly help operation like `hg log --patch`, delta computation (helping
pull/unbundle), linkrev adjustment (helping copy tracing).

A first round of benchmark for `hg log --patch --limit 1000` shows improvement
in the 10-20% range on "small" repository like pypy or mercurial and large
improvements (about 33%) for more complex ones like netbeans and mozilla's.

These speeds up are consistent with the improvement to `hg pull` (from a server
sending poor deltas) I saw benchmarking this last year. Further benchmark will
be run during the freeze.

I added some configuration in the experimental space to be able to further test
the effect of various tuning for now. This feature should fit well in the
"usage/resource profile" configuration that we should land next cycle.

When it does not provides a benefit the overhead of the cache seem to be around
2%, a small price for the big improvement. In addition I believe we could shave
most of this overhead with a more efficent lru implementation.

import unittest

from mercurial import policy

PartialDiscovery = policy.importrust('discovery', member='PartialDiscovery')

try:
    from mercurial.cext import parsers as cparsers
except ImportError:
    cparsers = None

# picked from test-parse-index2, copied rather than imported
# so that it stays stable even if test-parse-index2 changes or disappears.
data_non_inlined = (
    b'\x00\x00\x00\x01\x00\x00\x00\x00\x00\x01D\x19'
    b'\x00\x07e\x12\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff'
    b'\xff\xff\xff\xff\xd1\xf4\xbb\xb0\xbe\xfc\x13\xbd\x8c\xd3\x9d'
    b'\x0f\xcd\xd9;\x8c\x07\x8cJ/\x00\x00\x00\x00\x00\x00\x00\x00\x00'
    b'\x00\x00\x00\x00\x00\x00\x01D\x19\x00\x00\x00\x00\x00\xdf\x00'
    b'\x00\x01q\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x00\xff'
    b'\xff\xff\xff\xc1\x12\xb9\x04\x96\xa4Z1t\x91\xdfsJ\x90\xf0\x9bh'
    b'\x07l&\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
    b'\x00\x01D\xf8\x00\x00\x00\x00\x01\x1b\x00\x00\x01\xb8\x00\x00'
    b'\x00\x01\x00\x00\x00\x02\x00\x00\x00\x01\xff\xff\xff\xff\x02\n'
    b'\x0e\xc6&\xa1\x92\xae6\x0b\x02i\xfe-\xe5\xbao\x05\xd1\xe7\x00'
    b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01F'
    b'\x13\x00\x00\x00\x00\x01\xec\x00\x00\x03\x06\x00\x00\x00\x01'
    b'\x00\x00\x00\x03\x00\x00\x00\x02\xff\xff\xff\xff\x12\xcb\xeby1'
    b'\xb6\r\x98B\xcb\x07\xbd`\x8f\x92\xd9\xc4\x84\xbdK\x00\x00\x00'
    b'\x00\x00\x00\x00\x00\x00\x00\x00\x00'
)


class fakechangelog:
    def __init__(self, idx):
        self.index = idx


class fakerepo:
    def __init__(self, idx):
        """Just make so that self.changelog.index is the given idx."""
        self.changelog = fakechangelog(idx)


@unittest.skipIf(
    PartialDiscovery is None or cparsers is None,
    "rustext or the C Extension parsers module "
    "discovery relies on is not available",
)
class rustdiscoverytest(unittest.TestCase):
    """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 provided
    methods. Hence the very simple embedded index data is good enough.

    Algorithmic correctness is asserted by the Rust unit tests.
    """

    def parseindex(self):
        return cparsers.parse_index2(data_non_inlined, False)[0]

    def repo(self):
        return fakerepo(self.parseindex())

    def testindex(self):
        idx = self.parseindex()
        # checking our assumptions 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)},
        )

    def testaddcommonsmissings(self):
        disco = PartialDiscovery(self.repo(), [3], True)
        self.assertFalse(disco.hasinfo())
        self.assertFalse(disco.iscomplete())

        disco.addcommons([1])
        self.assertTrue(disco.hasinfo())
        self.assertFalse(disco.iscomplete())

        disco.addmissings([2])
        self.assertTrue(disco.hasinfo())
        self.assertTrue(disco.iscomplete())

        self.assertEqual(disco.commonheads(), {1})

    def testaddmissingsstats(self):
        disco = PartialDiscovery(self.repo(), [3], True)
        self.assertIsNone(disco.stats()['undecided'], None)

        disco.addmissings([2])
        self.assertEqual(disco.stats()['undecided'], 2)

    def testaddinfocommonfirst(self):
        disco = PartialDiscovery(self.repo(), [3], True)
        disco.addinfo([(1, True), (2, False)])
        self.assertTrue(disco.hasinfo())
        self.assertTrue(disco.iscomplete())
        self.assertEqual(disco.commonheads(), {1})

    def testaddinfomissingfirst(self):
        disco = PartialDiscovery(self.repo(), [3], True)
        disco.addinfo([(2, False), (1, True)])
        self.assertTrue(disco.hasinfo())
        self.assertTrue(disco.iscomplete())
        self.assertEqual(disco.commonheads(), {1})

    def testinitnorandom(self):
        PartialDiscovery(self.repo(), [3], True, randomize=False)


if __name__ == '__main__':
    import silenttestrunner

    silenttestrunner.main(__name__)