From 02a147039cc1694b1ea3d80636697b11e6a4461b Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Fri, 9 Feb 2024 10:51:00 +0000 Subject: [PATCH] Increase batching when fetching auth chains (#16893) This basically reverts a change that was in https://github.com/element-hq/synapse/pull/16833, where we reduced the batching. The smaller batching can cause performance issues on busy servers and databases. --- changelog.d/16893.bugfix | 1 + synapse/storage/databases/main/event_federation.py | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-) create mode 100644 changelog.d/16893.bugfix diff --git a/changelog.d/16893.bugfix b/changelog.d/16893.bugfix new file mode 100644 index 000000000000..7222cd765c20 --- /dev/null +++ b/changelog.d/16893.bugfix @@ -0,0 +1 @@ +Fix performance regression when fetching auth chains from the DB. Introduced in v1.100.0. diff --git a/synapse/storage/databases/main/event_federation.py b/synapse/storage/databases/main/event_federation.py index 12e882062a04..846c3f363a59 100644 --- a/synapse/storage/databases/main/event_federation.py +++ b/synapse/storage/databases/main/event_federation.py @@ -310,7 +310,7 @@ def _get_auth_chain_ids_using_cover_index_txn( # Add all linked chains reachable from initial set of chains. chains_to_fetch = set(event_chains.keys()) while chains_to_fetch: - batch2 = tuple(itertools.islice(chains_to_fetch, 100)) + batch2 = tuple(itertools.islice(chains_to_fetch, 1000)) chains_to_fetch.difference_update(batch2) clause, args = make_in_list_sql_clause( txn.database_engine, "origin_chain_id", batch2 @@ -593,7 +593,7 @@ def fetch_chain_info(events_to_fetch: Collection[str]) -> None: # the loop) chains_to_fetch = set(seen_chains) while chains_to_fetch: - batch2 = tuple(itertools.islice(chains_to_fetch, 100)) + batch2 = tuple(itertools.islice(chains_to_fetch, 1000)) clause, args = make_in_list_sql_clause( txn.database_engine, "origin_chain_id", batch2 )