sched_yield

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



NAME
       sched_yield - yield the processor

SYNOPSIS
       #include <sched.h>

       int sched_yield(void);

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

ERRORS
       In the Linux implementation, sched_yield() always succeeds.

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008.

NOTES
       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
       sched(7)

COLOPHON
       This page is part of release 5.03 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
       https://www.kernel.org/doc/man-pages/.



Linux                             2017-09-15                    SCHED_YIELD(2)