Seems all process blocked by a system service "fapolicy.d", when I stop the service, defunct process got disappeared and pending backends got released or moving on, and database started to accept new connection again. This fapolicy.d in RHEL8.4 is enabled by system admin to support security compliance requirements. systemctl stop fapolicyd , after that, everything go back to be normal soon. Regards, James -----Original Message----- From: James Pang (chaolpan) Sent: Monday, May 30, 2022 11:00 AM To: Tom Lane <tgl@xxxxxxxxxxxxx> Cc: Justin Pryzby <pryzby@xxxxxxxxxxxxx>; pgsql-performance@xxxxxxxxxxxxxxxxxxxx Subject: RE: postgres backend process hang on " D " state Maybe any bugs from these extensions ? I can try that removing all extensions, but we need these extensions. Thanks, James -----Original Message----- From: Tom Lane <tgl@xxxxxxxxxxxxx> Sent: Monday, May 30, 2022 10:21 AM To: James Pang (chaolpan) <chaolpan@xxxxxxxxx> Cc: Justin Pryzby <pryzby@xxxxxxxxxxxxx>; pgsql-performance@xxxxxxxxxxxxxxxxxxxx Subject: Re: postgres backend process hang on " D " state "James Pang (chaolpan)" <chaolpan@xxxxxxxxx> writes: > 1. extensions > shared_preload_libraries = 'orafce,pgaudit,pg_cron,pg_stat_statements,set_user' Can you still reproduce this if you remove all of those? regards, tom lane
