From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <49DCF4A7.807@domain.hid> Date: Wed, 08 Apr 2009 12:01:59 -0700 From: John Wojnaroski MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Xenomai-help] Excess getpid calls?? List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: xenomai@xenomai.org Hi We're running several apps with scheduled realtime task using rt_task_spawn() in a flight simulator. There are two apps each for a pilot and copilot and each app has 8 periodic tasks running at various duty cycles from 1Hz to 50Hz. A concern was raised as to whether the calls to getpid() were excessive. See trace ouput below.... <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< [1006]$ ps augx | grep -i copilot root 3561 24.7 5.6 51936 58108 ? RLl Apr01 2455:02 Source/Main/copilot --file=glass.cfg --window=0 0 2400 1050 hcsl 20859 0.0 0.0 1820 532 pts/4 S+ 09:55 0:00 grep -i copilot (09:55) : ~ [1007]$ sudo !! sudo strace -p 3561 -c Process 3561 attached - interrupt to quit Process 3561 detached % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 92.78 0.179969 2 90067 getpid 5.67 0.010999 5 2247 ioctl 1.55 0.003000 1 2247 gettimeofday 0.00 0.000000 0 9 poll ------ ----------- ----------- --------- --------- ---------------- 100.00 0.193968 94570 total >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> We have not bored down into the xenomai source to see exactly what is going on or where or how the calls are made as we've been quite happy with the performance and stability. Might someone shed a bit of light on the matter and should we be concerned? Thanks John W.