f4d0730bbc
Adapt the read stream logic for real AIO: - If AIO is enabled, we shouldn't issue advice, but if it isn't, we should continue issuing advice - AIO benefits from reading ahead with direct IO - If effective_io_concurrency=0, pass READ_BUFFERS_SYNCHRONOUSLY to StartReadBuffers() to ensure synchronous IO execution There are further improvements we should consider: - While in read_stream_look_ahead(), we can use AIO batch submission mode for increased efficiency. That however requires care to avoid deadlocks and thus done separately. - It can be beneficial to defer starting new IOs until we can issue multiple IOs at once. That however requires non-trivial heuristics to decide when to do so. Reviewed-by: Noah Misch <noah@leadboat.com> Co-authored-by: Andres Freund <andres@anarazel.de> Co-authored-by: Thomas Munro <thomas.munro@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/.