From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Mon, 11 Feb 2008 14:54:42 +0100
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-help] overhead
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To: Steven Seeger <sseeger@domain.hid>
Cc: xenomai@xenomai.org

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

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