From 294cdd7d0fffbaadf0f35202a30aab2863e6106a Mon Sep 17 00:00:00 2001 From: Fujii Masao Date: Mon, 28 Dec 2020 19:59:00 +0900 Subject: postgres_fdw: Fix connection leak. In postgres_fdw, the cached connections to foreign servers will not be closed until the local session exits if the user mappings or foreign servers that those connections depend on are dropped. Those connections can be leaked. To fix that connection leak issue, after a change to a pg_foreign_server or pg_user_mapping catalog entry, this commit makes postgres_fdw close the connections depending on that entry immediately if current transaction has not used those connections yet. Otherwise, mark those connections as invalid and then close them at the end of current transaction, since they cannot be closed in the midst of the transaction using them. Closed connections will be remade at the next opportunity if necessary. Back-patch to all supported branches. Author: Bharath Rupireddy Reviewed-by: Zhihong Yu, Zhijie Hou, Fujii Masao Discussion: https://postgr.es/m/CALj2ACVNcGH_6qLY-4_tXz8JLvA+4yeBThRfxMz7Oxbk1aHcpQ@mail.gmail.com --- contrib/postgres_fdw/sql/postgres_fdw.sql | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'contrib/postgres_fdw/sql/postgres_fdw.sql') diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 14e9ae76cdf..6d3154facc0 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -2427,3 +2427,17 @@ SELECT b, avg(a), max(a), count(*) FROM pagg_tab GROUP BY b HAVING sum(a) < 700 -- Clean-up RESET enable_partitionwise_aggregate; + +-- =================================================================== +-- test connection invalidation cases +-- =================================================================== +-- This test case is for closing the connection in pgfdw_xact_callback +BEGIN; +-- Connection xact depth becomes 1 i.e. the connection is in midst of the xact. +SELECT 1 FROM ft1 LIMIT 1; +-- Connection is not closed at the end of the alter statement in +-- pgfdw_inval_callback. That's because the connection is in midst of this +-- xact, it is just marked as invalid. +ALTER SERVER loopback OPTIONS (ADD use_remote_estimate 'off'); +-- The invalid connection gets closed in pgfdw_xact_callback during commit. +COMMIT; -- cgit v1.2.3