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.
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.
Programming for the real world - POSIX.4
by Bill O. Gallmeister, O'Reilly & Associates, Inc., ISBN 1-56592-074-0
COLOPHON
This page is part of release 3.14 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
