From bb7c976b7b2513f2d641fc72ea236508dceca3c3 Mon Sep 17 00:00:00 2001
From: Sait Talha Nisanci <s.talhanisanci@gmail.com>
Date: Fri, 17 Apr 2020 15:05:05 +0300
Subject: [PATCH] add invalidate_inactive_shared_connections udf

---
 .../connection/shared_connection_stats.c            | 13 +++++++++++++
 src/backend/distributed/sql/citus--9.2-4--9.3-2.sql |  1 +
 .../9.3-2.sql                                       | 10 ++++++++++
 .../latest.sql                                      | 10 ++++++++++
 4 files changed, 34 insertions(+)
 create mode 100644 src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/9.3-2.sql
 create mode 100644 src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/latest.sql

diff --git a/src/backend/distributed/connection/shared_connection_stats.c b/src/backend/distributed/connection/shared_connection_stats.c
index 92505caeb..89eb66435 100644
--- a/src/backend/distributed/connection/shared_connection_stats.c
+++ b/src/backend/distributed/connection/shared_connection_stats.c
@@ -109,6 +109,19 @@ static uint32 SharedConnectionHashHash(const void *key, Size keysize);
 
 
 PG_FUNCTION_INFO_V1(citus_remote_connection_stats);
+PG_FUNCTION_INFO_V1(invalidate_inactive_shared_connections);
+
+/*
+ * invalidate_inactive_shared_connections invalidates inactive
+ * and not used shared connections by removing from the global hash.
+ */
+Datum
+invalidate_inactive_shared_connections(PG_FUNCTION_ARGS)
+{
+	RemoveInactiveNodesFromSharedConnections();
+	PG_RETURN_VOID();
+}
+
 
 /*
  * citus_remote_connection_stats returns all the avaliable information about all
diff --git a/src/backend/distributed/sql/citus--9.2-4--9.3-2.sql b/src/backend/distributed/sql/citus--9.2-4--9.3-2.sql
index 8716ceb6c..c4e8a6527 100644
--- a/src/backend/distributed/sql/citus--9.2-4--9.3-2.sql
+++ b/src/backend/distributed/sql/citus--9.2-4--9.3-2.sql
@@ -9,6 +9,7 @@
 #include "udfs/worker_create_or_alter_role/9.3-2.sql"
 #include "udfs/truncate_local_data_after_distributing_table/9.3-2.sql"
 
+#include "udfs/invalidate_inactive_shared_connections/9.3-2.sql"
 -- add citus extension owner as a distributed object, if not already in there
 INSERT INTO citus.pg_dist_object SELECT
   (SELECT oid FROM pg_class WHERE relname = 'pg_authid') AS oid,
diff --git a/src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/9.3-2.sql b/src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/9.3-2.sql
new file mode 100644
index 000000000..54c1f8e1f
--- /dev/null
+++ b/src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/9.3-2.sql
@@ -0,0 +1,10 @@
+CREATE OR REPLACE FUNCTION pg_catalog.invalidate_inactive_shared_connections()
+RETURNS VOID
+LANGUAGE C STRICT
+AS 'MODULE_PATHNAME', $$invalidate_inactive_shared_connections$$;
+
+COMMENT ON FUNCTION pg_catalog.invalidate_inactive_shared_connections()
+     IS 'invalidated inactive shared connections';
+
+REVOKE ALL ON FUNCTION pg_catalog.invalidate_inactive_shared_connections()
+FROM PUBLIC;
diff --git a/src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/latest.sql b/src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/latest.sql
new file mode 100644
index 000000000..54c1f8e1f
--- /dev/null
+++ b/src/backend/distributed/sql/udfs/invalidate_inactive_shared_connections/latest.sql
@@ -0,0 +1,10 @@
+CREATE OR REPLACE FUNCTION pg_catalog.invalidate_inactive_shared_connections()
+RETURNS VOID
+LANGUAGE C STRICT
+AS 'MODULE_PATHNAME', $$invalidate_inactive_shared_connections$$;
+
+COMMENT ON FUNCTION pg_catalog.invalidate_inactive_shared_connections()
+     IS 'invalidated inactive shared connections';
+
+REVOKE ALL ON FUNCTION pg_catalog.invalidate_inactive_shared_connections()
+FROM PUBLIC;