From 3e6ee8ff88c41ad1fca8c055520be952ab21b705 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Mon, 6 May 2024 12:56:52 +0100 Subject: Add optimisation to `StreamChangeCache` (#17130) When there have been lots of changes compared with the number of entities, we can do a fast(er) path. Locally I ran some benchmarking, and the comparison seems to give the best determination of which method we use. --- tests/util/test_stream_change_cache.py | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) (limited to 'tests') diff --git a/tests/util/test_stream_change_cache.py b/tests/util/test_stream_change_cache.py index 3df053493b..5d38718a50 100644 --- a/tests/util/test_stream_change_cache.py +++ b/tests/util/test_stream_change_cache.py @@ -1,3 +1,5 @@ +from parameterized import parameterized + from synapse.util.caches.stream_change_cache import StreamChangeCache from tests import unittest @@ -161,7 +163,8 @@ class StreamChangeCacheTests(unittest.HomeserverTestCase): self.assertFalse(cache.has_any_entity_changed(2)) self.assertFalse(cache.has_any_entity_changed(3)) - def test_get_entities_changed(self) -> None: + @parameterized.expand([(0,), (1000000000,)]) + def test_get_entities_changed(self, perf_factor: int) -> None: """ StreamChangeCache.get_entities_changed will return the entities in the given list that have changed since the provided stream ID. If the @@ -178,7 +181,9 @@ class StreamChangeCacheTests(unittest.HomeserverTestCase): # get the ones after that point. self.assertEqual( cache.get_entities_changed( - ["user@foo.com", "bar@baz.net", "user@elsewhere.org"], stream_pos=2 + ["user@foo.com", "bar@baz.net", "user@elsewhere.org"], + stream_pos=2, + _perf_factor=perf_factor, ), {"bar@baz.net", "user@elsewhere.org"}, ) @@ -195,6 +200,7 @@ class StreamChangeCacheTests(unittest.HomeserverTestCase): "not@here.website", ], stream_pos=2, + _perf_factor=perf_factor, ), {"bar@baz.net", "user@elsewhere.org"}, ) @@ -210,6 +216,7 @@ class StreamChangeCacheTests(unittest.HomeserverTestCase): "not@here.website", ], stream_pos=0, + _perf_factor=perf_factor, ), {"user@foo.com", "bar@baz.net", "user@elsewhere.org", "not@here.website"}, ) @@ -217,7 +224,11 @@ class StreamChangeCacheTests(unittest.HomeserverTestCase): # Query a subset of the entries mid-way through the stream. We should # only get back the subset. self.assertEqual( - cache.get_entities_changed(["bar@baz.net"], stream_pos=2), + cache.get_entities_changed( + ["bar@baz.net"], + stream_pos=2, + _perf_factor=perf_factor, + ), {"bar@baz.net"}, ) -- cgit 1.4.1