Copyright (C) Tom Bjorkholm & Markus Kuhn, 1996 %%%LICENSE_START(GPLv2+_DOC_FULL) This is free documentation; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU General Public License's references to "object code" and "executables" are to be interpreted as the output of any document formatting or typesetting system, including i...
NAMEsched_yield - yield the processor
DESCRIPTIONsched_yield() causes the calling thread to relinquish the CPU. The thread is moved to the end of the queue for its static priority and a new thread gets to run.
RETURN VALUEOn success, sched_yield() returns 0. On error, -1 is returned, and errno is set appropriately.
ERRORSIn the Linux implementation, sched_yield() always succeeds.
CONFORMING TOPOSIX.1-2001, POSIX.1-2008.
NOTESIf the calling thread is the only thread in the highest priority list at that time, it will continue to run after a call to sched_yield().
POSIX systems on which sched_yield() is available define _POSIX_PRIORITY_SCHEDULING in <unistd.h>.
Strategic calls to sched_yield() can improve performance by giving other threads or processes a chance to run when (heavily) contended resources (e.g., mutexes) have been released by the caller. Avoid calling sched_yield() unnecessarily or inappropriately (e.g., when resources needed by other schedulable threads are still held by the caller), since doing so will result in unnecessary context switches, which will degrade system performance.