On Fri, 2005-08-12 at 08:26 +0200, Peter Svensson wrote: > > Since Linux is not RTOS, why some folks are using this "-p" switch? > > It has no effect on standard Linux box. > > Linux is not a hard realtime os with guaranteed timing. What the -p > flag > does is to request the realtime scheduler. This means a process wil > no > longer be subjected to the stanadrd unix scheduling but rather use a > strict priority scheduling. The net result is that once a process > using > the realtime scheduler is ready to run the kernel wihh schedule it as > soon > as possible. It will only be preempted by realtime processes of the > same > or better priority. > > With the addition of the lowlatency patches the worst case latency > for > userspace applications is very low. The remaining difference between > a > hard RT os is the guarantees it can make. > > Peter
Thanks for the explanation, it makes sense now. Though is the way to verify that asterisk is running with "-p" switch? I've modified the startup script to start asterisk with "-p"; however asterisk starts several sub-precess-ID's. Do the sup-process-ID's are effected by the "-p" switch? I run schedtool (12189 is asterisk PID with -p switch) and it shows: schedtool 12189 PID 12189: PRIO 0, POLICY N: SCHED_NORMAL, NICE -15, AFFINITY 0x1 I run schedtool (27421 is asterisk PID without -p switch) and it shows: schedtool 27421 PID 27421: PRIO 0, POLICY N: SCHED_NORMAL, NICE -15, AFFINITY 0x1 I can verify that "nice" has taken effect but PRIO shows in both cases "0" -- #Joseph _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users