postgresql/contrib/worker_spi/worker_spi--1.0.sql

/* contrib/worker_spi/worker_spi--1.0.sql */

-- complain if script is sourced in psql, rather than via CREATE EXTENSION
\echo Use "CREATE EXTENSION worker_spi" to load this file. \quit

CREATE FUNCTION worker_spi_launch(pg_catalog.int4)
RETURNS pg_catalog.int4 STRICT
AS 'MODULE_PATHNAME'
LANGUAGE C;
Allow background workers to be started dynamically. There is a new API, RegisterDynamicBackgroundWorker, which allows an ordinary user backend to register a new background writer during normal running. This means that it's no longer necessary for all background workers to be registered during processing of shared_preload_libraries, although the option of registering workers at that time remains available. When a background worker exits and will not be restarted, the slot previously used by that background worker is automatically released and becomes available for reuse. Slots used by background workers that are configured for automatic restart can't (yet) be released without shutting down the system. This commit adds a new source file, bgworker.c, and moves some of the existing control logic for background workers there. Previously, there was little enough logic that it made sense to keep everything in postmaster.c, but not any more. This commit also makes the worker_spi contrib module into an extension and adds a new function, worker_spi_launch, which can be used to demonstrate the new facility. 2013-07-17 01:02:15 +08:00			`/* contrib/worker_spi/worker_spi--1.0.sql */`

			`-- complain if script is sourced in psql, rather than via CREATE EXTENSION`
			`\echo Use "CREATE EXTENSION worker_spi" to load this file. \quit`

			`CREATE FUNCTION worker_spi_launch(pg_catalog.int4)`
Allow discovery of whether a dynamic background worker is running. Using the infrastructure provided by this patch, it's possible either to wait for the startup of a dynamically-registered background worker, or to poll the status of such a worker without waiting. In either case, the current PID of the worker process can also be obtained. As usual, worker_spi is updated to demonstrate the new functionality. Patch by me. Review by Andres Freund. 2013-08-29 02:08:13 +08:00			`RETURNS pg_catalog.int4 STRICT`
Allow background workers to be started dynamically. There is a new API, RegisterDynamicBackgroundWorker, which allows an ordinary user backend to register a new background writer during normal running. This means that it's no longer necessary for all background workers to be registered during processing of shared_preload_libraries, although the option of registering workers at that time remains available. When a background worker exits and will not be restarted, the slot previously used by that background worker is automatically released and becomes available for reuse. Slots used by background workers that are configured for automatic restart can't (yet) be released without shutting down the system. This commit adds a new source file, bgworker.c, and moves some of the existing control logic for background workers there. Previously, there was little enough logic that it made sense to keep everything in postmaster.c, but not any more. This commit also makes the worker_spi contrib module into an extension and adds a new function, worker_spi_launch, which can be used to demonstrate the new facility. 2013-07-17 01:02:15 +08:00			`AS 'MODULE_PATHNAME'`
			`LANGUAGE C;`