The overhead was measured by only comparing cpu usage between tasks from the statistics collection stuff. There are some userland tasks running at 8khz, so apparently this is a problem for Xenomai on this board. I had no problem at all with these tasks in kernel space under rtai.
There are no faults at all under /proc/xenomai/faults. The main way I can tell something is wrong is that if my three fast tasks are running (8 khz in kernel space, 8 khz in userspace, and 50 hz in userspace) then a lower priority task will timeout and trip a watchdog. If I remove the IO routines from the 50hz task, then the others can still run. Steven > -----Original Message----- > From: Jan Kiszka [mailto:[EMAIL PROTECTED] > Sent: Monday, February 11, 2008 6:55 AM > To: Steven Seeger > Cc: [email protected] > Subject: Re: [Xenomai-help] overhead > > Steven Seeger wrote: > > Is it normal for Xenomai to have significant overhead in userspace > > compared to older software running RTAI with all realtime threads in > > kernel modules? My application makes heavy use of inb/outb with iopl(). > > Significant overhead in user land can come from significant task > switches or a significant number of syscalls. But direct I/O should not > bite you. Any suspicious number of faults under /proc/xenomai/faults? > > How did you measure the overhead in both systems? > > Jan > > -- > Siemens AG, Corporate Technology, CT SE 2 > Corporate Competence Center Embedded Linux _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
