1SCHED_YIELD(2) Linux Programmer's Manual SCHED_YIELD(2)
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6 sched_yield - yield the processor
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9 #include <sched.h>
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11 int sched_yield(void);
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14 sched_yield() causes the calling thread to relinquish the CPU. The
15 thread is moved to the end of the queue for its static priority and a
16 new thread gets to run.
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19 On success, sched_yield() returns 0. On error, -1 is returned, and er‐
20 rno is set to indicate the error.
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23 In the Linux implementation, sched_yield() always succeeds.
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26 POSIX.1-2001, POSIX.1-2008.
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29 If the calling thread is the only thread in the highest priority list
30 at that time, it will continue to run after a call to sched_yield().
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32 POSIX systems on which sched_yield() is available define _POSIX_PRIOR‐
33 ITY_SCHEDULING in <unistd.h>.
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35 Strategic calls to sched_yield() can improve performance by giving
36 other threads or processes a chance to run when (heavily) contended re‐
37 sources (e.g., mutexes) have been released by the caller. Avoid call‐
38 ing sched_yield() unnecessarily or inappropriately (e.g., when re‐
39 sources needed by other schedulable threads are still held by the
40 caller), since doing so will result in unnecessary context switches,
41 which will degrade system performance.
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43 sched_yield() is intended for use with real-time scheduling policies
44 (i.e., SCHED_FIFO or SCHED_RR). Use of sched_yield() with nondetermin‐
45 istic scheduling policies such as SCHED_OTHER is unspecified and very
46 likely means your application design is broken.
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49 sched(7)
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52 This page is part of release 5.13 of the Linux man-pages project. A
53 description of the project, information about reporting bugs, and the
54 latest version of this page, can be found at
55 https://www.kernel.org/doc/man-pages/.
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59Linux 2021-03-22 SCHED_YIELD(2)