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    <p>That's the basic template for how I would do it but after searching around I found next to no code examples so I guess the verdict is out on whether it is best or not.</p> <p>The problem is that boost::thread does not have a constructor that allows pthead attributes to be passed in at thread creation so you have to make changes after the thread starts. The only other way I know to get around that is through the process/thread schedule inheritance. Unless directed otherwise, new threads will inherit the schedule/priority of their creator so you could change the current thread before creating worker threads and then change back if you want. Seems awkward but it is an alternative.</p> <p>Here's a hack of an example that hopefully demostrates both. You may need to change policy and priority as appropriate and run as root.</p> <p>Be careful with the way you set the priority. Various restrictions apply.</p> <pre><code>#include &lt;iostream&gt; #include &lt;boost/thread/thread.hpp&gt; #include &lt;unistd.h&gt; #include &lt;sched.h&gt; #include &lt;cstdio&gt; void* threadfunc() { sleep(5); } void displayAndChange(boost::thread&amp; daThread) { int retcode; int policy; pthread_t threadID = (pthread_t) daThread.native_handle(); struct sched_param param; if ((retcode = pthread_getschedparam(threadID, &amp;policy, &amp;param)) != 0) { errno = retcode; perror("pthread_getschedparam"); exit(EXIT_FAILURE); } std::cout &lt;&lt; "INHERITED: "; std::cout &lt;&lt; "policy=" &lt;&lt; ((policy == SCHED_FIFO) ? "SCHED_FIFO" : (policy == SCHED_RR) ? "SCHED_RR" : (policy == SCHED_OTHER) ? "SCHED_OTHER" : "???") &lt;&lt; ", priority=" &lt;&lt; param.sched_priority &lt;&lt; std::endl; policy = SCHED_FIFO; param.sched_priority = 4; if ((retcode = pthread_setschedparam(threadID, policy, &amp;param)) != 0) { errno = retcode; perror("pthread_setschedparam"); exit(EXIT_FAILURE); } std::cout &lt;&lt; " CHANGED: "; std::cout &lt;&lt; "policy=" &lt;&lt; ((policy == SCHED_FIFO) ? "SCHED_FIFO" : (policy == SCHED_RR) ? "SCHED_RR" : (policy == SCHED_OTHER) ? "SCHED_OTHER" : "???") &lt;&lt; ", priority=" &lt;&lt; param.sched_priority &lt;&lt; std::endl; } int main(int argc, char* argv[]) { int policy, res; struct sched_param param; if ((policy = sched_getscheduler(getpid())) == -1) { perror("sched_getscheduler"); exit(EXIT_FAILURE); } if ((res = sched_getparam(getpid(), &amp;param)) == -1) { perror("sched_getparam"); exit(EXIT_FAILURE); } std::cout &lt;&lt; " ORIGINAL: "; std::cout &lt;&lt; "policy=" &lt;&lt; ((policy == SCHED_FIFO) ? "SCHED_FIFO" : (policy == SCHED_RR) ? "SCHED_RR" : (policy == SCHED_OTHER) ? "SCHED_OTHER" : "???") &lt;&lt; ", priority=" &lt;&lt; param.sched_priority &lt;&lt; std::endl; policy = SCHED_RR; param.sched_priority = 2; if ((res = sched_setscheduler(getpid(), policy, &amp;param)) == -1) { perror("sched_setscheduler"); exit(EXIT_FAILURE); } boost::thread t1(&amp;threadfunc); displayAndChange(t1); t1.join(); return 0; } </code></pre>
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    1. COI was just looking for a quick sample not to go trough manual pages and found this useful. Thanks.
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