sched_yield(2) — Linux manual page


SCHED_YIELD(2)            Linux Programmer's Manual           SCHED_YIELD(2)

NAME         top

       sched_yield - yield the processor

SYNOPSIS         top

       #include <sched.h>

       int sched_yield(void);

DESCRIPTION         top

       sched_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 VALUE         top

       On success, sched_yield() returns 0.  On error, -1 is returned, and
       errno is set appropriately.

ERRORS         top

       In the Linux implementation, sched_yield() always succeeds.

CONFORMING TO         top

       POSIX.1-2001, POSIX.1-2008.

NOTES         top

       If 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.

       sched_yield() is intended for use with real-time scheduling policies
       (i.e., SCHED_FIFO or SCHED_RR).  Use of sched_yield() with
       nondeterministic scheduling policies such as SCHED_OTHER is
       unspecified and very likely means your application design is broken.

SEE ALSO         top


COLOPHON         top

       This page is part of release 5.09 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at

Linux                            2017-09-15                   SCHED_YIELD(2)

Pages that refer to this page: getrlimit(2)prlimit(2)prlimit64(2)sched_getattr(2)sched_getscheduler(2)sched_setattr(2)sched_setscheduler(2)setrlimit(2)syscalls(2)ugetrlimit(2)pthread_yield(3)vlimit(3)sched(7)