From db25e30a256047454a9b09b579856d6cce0a6a7b Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Wed, 8 May 2024 16:04:35 +0100 Subject: [PATCH 1/3] Perf improvement to getting auth chains --- .../databases/main/event_federation.py | 33 +++++++++++++++---- 1 file changed, 26 insertions(+), 7 deletions(-) diff --git a/synapse/storage/databases/main/event_federation.py b/synapse/storage/databases/main/event_federation.py index fb132ef090..68f30d893c 100644 --- a/synapse/storage/databases/main/event_federation.py +++ b/synapse/storage/databases/main/event_federation.py @@ -283,7 +283,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas # A map from chain ID to max sequence number *reachable* from any event ID. chains: Dict[int, int] = {} - for links in self._get_chain_links(txn, set(event_chains.keys())): + for links in self._get_chain_links(txn, event_chains.keys()): for chain_id in links: if chain_id not in event_chains: continue @@ -335,7 +335,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas @classmethod def _get_chain_links( - cls, txn: LoggingTransaction, chains_to_fetch: Set[int] + cls, txn: LoggingTransaction, chains_to_fetch: Collection[int] ) -> Generator[Dict[int, List[Tuple[int, int, int]]], None, None]: """Fetch all auth chain links from the given set of chains, and all links from those chains, recursively. @@ -371,9 +371,27 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas INNER JOIN event_auth_chain_links ON (chain_id = origin_chain_id) """ - while chains_to_fetch: - batch2 = tuple(itertools.islice(chains_to_fetch, 1000)) - chains_to_fetch.difference_update(batch2) + # We fetch the links in batches. Separate batches will likely fetch the + # same set of links (e.g. they'll always pull in the links to create + # event). To try and minimize the amount of redundant links, we sort the + # chain IDs in reverse, as there will be a correlation between the order + # of chain IDs and links (i.e., higher chain IDs are more likely to + # depend on lower chain IDs than vice versa). + BATCH_SIZE = 1000 + chains_to_fetch_list = list(chains_to_fetch) + chains_to_fetch_list.sort(reverse=True) + + seen_chains: Set[int] = set() + while chains_to_fetch_list: + batch2 = [ + c for c in chains_to_fetch_list[-BATCH_SIZE:] if c not in seen_chains + ] + chains_to_fetch_list = chains_to_fetch_list[:-BATCH_SIZE] + while len(batch2) < BATCH_SIZE and chains_to_fetch_list: + chain_id = chains_to_fetch_list.pop() + if chain_id not in seen_chains: + batch2.append(chain_id) + clause, args = make_in_list_sql_clause( txn.database_engine, "origin_chain_id", batch2 ) @@ -391,7 +409,8 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas (origin_sequence_number, target_chain_id, target_sequence_number) ) - chains_to_fetch.difference_update(links) + seen_chains.update(links) + seen_chains.update(batch2) yield links @@ -581,7 +600,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas # are reachable from any event. # (We need to take a copy of `seen_chains` as the function mutates it) - for links in self._get_chain_links(txn, set(seen_chains)): + for links in self._get_chain_links(txn, seen_chains): for chains in set_to_chain: for chain_id in links: if chain_id not in chains: From 202a09cdb3adb7adc8270b5cf5cdf86637f5f1c3 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Wed, 8 May 2024 16:05:24 +0100 Subject: [PATCH 2/3] Newsfile --- changelog.d/17169.misc | 1 + 1 file changed, 1 insertion(+) create mode 100644 changelog.d/17169.misc diff --git a/changelog.d/17169.misc b/changelog.d/17169.misc new file mode 100644 index 0000000000..6b06b002ea --- /dev/null +++ b/changelog.d/17169.misc @@ -0,0 +1 @@ +Add database performance improvement when fetching auth chains. From ca79b4d87df814ae69dd093253d500108d48e461 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Wed, 8 May 2024 16:31:59 +0100 Subject: [PATCH 3/3] Use a sortedset instead --- .../databases/main/event_federation.py | 28 +++---- tests/storage/test_purge.py | 74 +++++++++++++++++++ 2 files changed, 84 insertions(+), 18 deletions(-) diff --git a/synapse/storage/databases/main/event_federation.py b/synapse/storage/databases/main/event_federation.py index 68f30d893c..3dd53f2038 100644 --- a/synapse/storage/databases/main/event_federation.py +++ b/synapse/storage/databases/main/event_federation.py @@ -39,6 +39,7 @@ from typing import ( import attr from prometheus_client import Counter, Gauge +from sortedcontainers import SortedSet from synapse.api.constants import MAX_DEPTH from synapse.api.errors import StoreError @@ -373,24 +374,16 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas # We fetch the links in batches. Separate batches will likely fetch the # same set of links (e.g. they'll always pull in the links to create - # event). To try and minimize the amount of redundant links, we sort the - # chain IDs in reverse, as there will be a correlation between the order - # of chain IDs and links (i.e., higher chain IDs are more likely to - # depend on lower chain IDs than vice versa). + # event). To try and minimize the amount of redundant links, we query + # the chain IDs in reverse order, as there will be a correlation between + # the order of chain IDs and links (i.e., higher chain IDs are more + # likely to depend on lower chain IDs than vice versa). BATCH_SIZE = 1000 - chains_to_fetch_list = list(chains_to_fetch) - chains_to_fetch_list.sort(reverse=True) + chains_to_fetch_sorted = SortedSet(chains_to_fetch) - seen_chains: Set[int] = set() - while chains_to_fetch_list: - batch2 = [ - c for c in chains_to_fetch_list[-BATCH_SIZE:] if c not in seen_chains - ] - chains_to_fetch_list = chains_to_fetch_list[:-BATCH_SIZE] - while len(batch2) < BATCH_SIZE and chains_to_fetch_list: - chain_id = chains_to_fetch_list.pop() - if chain_id not in seen_chains: - batch2.append(chain_id) + while chains_to_fetch_sorted: + batch2 = list(chains_to_fetch_sorted.islice(-BATCH_SIZE)) + chains_to_fetch_sorted.difference_update(batch2) clause, args = make_in_list_sql_clause( txn.database_engine, "origin_chain_id", batch2 @@ -409,8 +402,7 @@ class EventFederationWorkerStore(SignatureWorkerStore, EventsWorkerStore, SQLBas (origin_sequence_number, target_chain_id, target_sequence_number) ) - seen_chains.update(links) - seen_chains.update(batch2) + chains_to_fetch_sorted.difference_update(links) yield links diff --git a/tests/storage/test_purge.py b/tests/storage/test_purge.py index 080d5640a5..9fa69f6581 100644 --- a/tests/storage/test_purge.py +++ b/tests/storage/test_purge.py @@ -25,6 +25,7 @@ from synapse.rest.client import room from synapse.server import HomeServer from synapse.util import Clock +from tests.test_utils.event_injection import inject_event from tests.unittest import HomeserverTestCase @@ -128,3 +129,76 @@ class PurgeTests(HomeserverTestCase): self.store._invalidate_local_get_event_cache(create_event.event_id) self.get_failure(self.store.get_event(create_event.event_id), NotFoundError) self.get_failure(self.store.get_event(first["event_id"]), NotFoundError) + + def test_state_groups_state_decreases(self) -> None: + response = self.helper.send(self.room_id, body="first") + first_event_id = response["event_id"] + + batches = [] + + previous_event_id = first_event_id + for i in range(50): + state_event1 = self.get_success( + inject_event( + self.hs, + type="test.state", + sender=self.user_id, + state_key="", + room_id=self.room_id, + content={"key": i, "e": 1}, + prev_event_ids=[previous_event_id], + origin_server_ts=1, + ) + ) + + state_event2 = self.get_success( + inject_event( + self.hs, + type="test.state", + sender=self.user_id, + state_key="", + room_id=self.room_id, + content={"key": i, "e": 2}, + prev_event_ids=[previous_event_id], + origin_server_ts=2, + ) + ) + + # print(state_event2.origin_server_ts - state_event1.origin_server_ts) + + message_event = self.get_success( + inject_event( + self.hs, + type="dummy_event", + sender=self.user_id, + room_id=self.room_id, + content={}, + prev_event_ids=[state_event1.event_id, state_event2.event_id], + ) + ) + + token = self.get_success( + self.store.get_topological_token_for_event(state_event1.event_id) + ) + batches.append(token) + + previous_event_id = message_event.event_id + + self.helper.send(self.room_id, body="last event") + + def count_state_groups() -> int: + sql = "SELECT COUNT(*) FROM state_groups_state WHERE room_id = ?" + rows = self.get_success( + self.store.db_pool.execute("test_deduplicate_joins", sql, self.room_id) + ) + return rows[0][0] + + print(count_state_groups()) + for token in batches: + token_str = self.get_success(token.to_string(self.hs.get_datastores().main)) + self.get_success( + self._storage_controllers.purge_events.purge_history( + self.room_id, token_str, False + ) + ) + print(count_state_groups())