Btree vacuum processes all index pages in physical order. Now it uses the read stream API to get the next buffer instead of explicitly invoking ReadBuffer(). It is possible for concurrent insertions to cause page splits during index vacuuming. This can lead to index entries that have yet to be vacuumed being moved to pages that have already been vacuumed. Btree vacuum code handles this by backtracking to reprocess those pages. So, while sequentially encountered pages are now read through the read stream API, backtracked pages are still read with explicit ReadBuffer() calls. Author: Andrey Borodin <x4mmm@yandex-team.ru> Reviewed-by: Melanie Plageman <melanieplageman@gmail.com> Reviewed-by: Junwang Zhao <zhjwpku@gmail.com> Reviewed-by: Kirill Reshke <reshkekirill@gmail.com> Discussion: https://postgr.es/m/flat/CAAKRu_bW1UOyup%3DjdFw%2BkOF9bCaAm%3D9UpiyZtbPMn8n_vnP%2Big%40mail.gmail.com#3b3a84132fc683b3ee5b40bc4c2ea2a5
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/.