If the running query is not at a point where it will check for interrupts, it will just keep running. Test: Fix occasional 073.pg_terminate_backend test failure. The two tasks above cannot drop/created databases because the main command still holds the connection. The workaround I can see on the build machine is this set of commands (create the dev database too). Regardless of whatever issues you might have, pg_cancel_backend cancels the backend's current query. The postgres server uses SIGQUIT to tell subordinate server processes to terminate without normal cleanup. connection . client application is hanging (or paused) and does not receive any data from the server, in this case keepalive works fine and the send() syscall will never end, even when a TERM signal was sent to it, because PostgreSQL is using SA_RESTARTflag for signal processing and SO_SNDTIMEO is not used at all (see man 7 signal). SELECT pg_terminate_backend(25263) FROM pg_stat_activity WHERE -- don't kill my own connection! (Tatsuo Ishii) This issue can be reproduced with the following steps: Shutdown all backends. To terminate a backend process cleanly, send SIGTERM to that process. Hi Team , We are observing long running process hung in active state on one of our db from last two days Revisiting this, there are places where PostgreSQL backends are doing work … Depending on the query, that might be anything from seconds to hours before it stops. Connect to pgpool with invalid client. Examples. pg_terminate_backend() or pg_cancel_backend() (those functions return true but the entries in pg_stat_activity remain), and they persist long after the client application has exited - there were some I found on a staging server that were a month old, and were only resolved by Abandoned replication slots: A replication slot is a data structure that keeps the PostgreSQL server from discarding information that is still needed by a … See also pg_cancel_backend and pg_terminate_backend in Section 9.26.2 for the SQL-callable equivalents of these two actions. Due to that, cancel often seems like it didn't work. Two processes work on app_test and app_test2 database. You want pg_terminate_backend.. More fundamentally, it seems like you have an application problem or a connection pooler problem, but you haven't described them enough for us to give advice. general - pg_terminate_backend not working, pg_terminate_backend not working. I have used pcp_attach_node with pgpool's port number, not pcp's. You can use the pg_terminate_backend() function to terminate the database session that is blocking your VACUUM. The first method we can use is SELECT pg_cancel_backend(pid).It simply cancels the query and keeps the connection untouched. In case it does not work, you can be a bit more aggressive by killing the connection: ActiveRecord :: Base . To cancel a currently running query, first retrieve the process ID for the query that you want to cancel. Terminate tells the backend itself to … END), you can terminate the session in which the query is running by using the PG_TERMINATE_BACKEND function. But an idle backend doesn't have a current query, which is what makes it idle. 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