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.

SEE ALSO

       sched(7)

COLOPHON

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Linux                                              2015-08-08                                     SCHED_YIELD(2)