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 5.10 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)