a78af04270
Previously, only backends, autovacuum workers, and background workers had an entry in the PMChildFlags array. With this commit, all postmaster child processes, including all the aux processes, have an entry. Dead-end backends still don't get an entry, though, and other processes that don't touch shared memory will never mark their PMChildFlags entry as active. We now maintain separate freelists for different kinds of child processes. That ensures that there are always slots available for autovacuum and background workers. Previously, pre-authentication backends could prevent autovacuum or background workers from starting up, by using up all the slots. The code to manage the slots in the postmaster process is in a new pmchild.c source file. Because postmaster.c is just so large. Assigning pmsignal slot numbers is now pmchild.c's responsibility. This replaces the PMChildInUse array in pmsignal.c. Some of the comments in postmaster.c still talked about the "stats process", but that was removed in commit 5891c7a8ed. Fix those while we're at it. Reviewed-by: Andres Freund <andres@anarazel.de> Discussion: https://www.postgresql.org/message-id/a102f15f-eac4-4ff2-af02-f9ff209ec66f@iki.fi
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.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.