Calculate the insert threshold for triggering an autovacuum of a relation based on the number of unfrozen pages. By only considering the unfrozen portion of the table when calculating how many tuples to add to the insert threshold, we can trigger more frequent vacuums of insert-heavy tables. This increases the chances of vacuuming those pages when they still reside in shared buffers This also increases the number of autovacuums triggered by tuples inserted and not by wraparound risk. We prefer to freeze these pages during insert-triggered autovacuums, as anti-wraparound vacuums are not automatically canceled by conflicting lock requests. We calculate the unfrozen percentage of the table using the recently added (99f8f3fbbc8f) relallfrozen column of pg_class. Author: Melanie Plageman <melanieplageman@gmail.com> Reviewed-by: Nathan Bossart <nathandbossart@gmail.com> Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com> Reviewed-by: Robert Treat <rob@xzilla.net> Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com> Discussion: https://postgr.es/m/flat/CAAKRu_aj-P7YyBz_cPNwztz6ohP%2BvWis%3Diz3YcomkB3NpYA--w%40mail.gmail.com
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/.