8f1537d10e
The tests added in 9f8a050f68d failed nearly reliably on FreeBSD in CI, and occasionally on the buildfarm. That turns out to be caused not by a bug in the test, but by a longstanding bug in recovery conflict handling. The standby timeout handler, used by ResolveRecoveryConflictWithBufferPin(), executed SendRecoveryConflictWithBufferPin() inside a signal handler. A bad idea, because the deadlock timeout handler (or a spurious latch set) could have interrupted ProcWaitForSignal(). If unlucky that could cause a self-deadlock on ProcArrayLock, if the deadlock check is in SendRecoveryConflictWithBufferPin()->CancelDBBackends(). To fix, set a flag in StandbyTimeoutHandler(), and check the flag in ResolveRecoveryConflictWithBufferPin(). Subsequently the recovery conflict tests will be backpatched. Discussion: https://postgr.es/m/20220413002626.udl7lll7f3o7nre7@alap3.anarazel.de Backpatch: 10-
PostgreSQL Database Management System ===================================== This directory contains the source code distribution of the PostgreSQL database management system. PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.