From 214d8c706077a9215541a283650f5c17e43ba8a7 Mon Sep 17 00:00:00 2001 From: "Olivier Wilkinson (reivilibre)" Date: Fri, 24 Mar 2023 11:44:01 +0000 Subject: [PATCH 1/2] Use TRUNCATE on Postgres for the user directory tables --- synapse/storage/databases/main/user_directory.py | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/synapse/storage/databases/main/user_directory.py b/synapse/storage/databases/main/user_directory.py index 97f09b73dde6..9fced4b99718 100644 --- a/synapse/storage/databases/main/user_directory.py +++ b/synapse/storage/databases/main/user_directory.py @@ -698,10 +698,17 @@ async def delete_all_from_user_dir(self) -> None: """Delete the entire user directory""" def _delete_all_from_user_dir_txn(txn: LoggingTransaction) -> None: - txn.execute("DELETE FROM user_directory") - txn.execute("DELETE FROM user_directory_search") - txn.execute("DELETE FROM users_in_public_rooms") - txn.execute("DELETE FROM users_who_share_private_rooms") + # SQLite doesn't support TRUNCATE. + # On Postgres, DELETE FROM does a table scan but TRUNCATE is more efficient. + truncate = ( + "DELETE FROM" + if isinstance(self.database_engine, Sqlite3Engine) + else "TRUNCATE" + ) + txn.execute(f"{truncate} user_directory") + txn.execute(f"{truncate} user_directory_search") + txn.execute(f"{truncate} users_in_public_rooms") + txn.execute(f"{truncate} users_who_share_private_rooms") txn.call_after(self.get_user_in_directory.invalidate_all) await self.db_pool.runInteraction( From 804800d36f00b49563a6dc0bebc04efaccf55548 Mon Sep 17 00:00:00 2001 From: "Olivier Wilkinson (reivilibre)" Date: Fri, 24 Mar 2023 11:44:30 +0000 Subject: [PATCH 2/2] Newsfile Signed-off-by: Olivier Wilkinson (reivilibre) --- changelog.d/15316.misc | 1 + 1 file changed, 1 insertion(+) create mode 100644 changelog.d/15316.misc diff --git a/changelog.d/15316.misc b/changelog.d/15316.misc new file mode 100644 index 000000000000..1f408739f0bc --- /dev/null +++ b/changelog.d/15316.misc @@ -0,0 +1 @@ +As an optimisation, use `TRUNCATE` on Postgres when clearing the user directory tables. \ No newline at end of file