From mboxrd@z Thu Jan  1 00:00:00 1970
From: Robert Schwebel <r.schwebel@pengutronix.de>
Subject: Re: High latencies on MPC5200 with patch-2.6.24-rc5-rt1
Date: Thu, 10 Jan 2008 15:35:27 +0100
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To: Wolfgang Grandegger <wg@grandegger.com>
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On Thu, Jan 10, 2008 at 02:17:02PM +0100, Wolfgang Grandegger wrote:
> Unfortunately, it doesn't really help on my Icecube board.
> 
> bash-3.00# ./cyclictest -n -p80 -i1000
> 129.85 93.18 38.05 4/45 6354
> 130.41 162.23 83.05 3/49 8395
> T: 0 ( 4621) P:80 I:1000 C: 477097 Min:     25 Act:   64 Avg:   67 Max:
>     286
> 
> bash-3.00# ./hackbench 10
> Time: 95.402
> 
> Could you run your cyclictest much longer?

I'll re-test with your parameters.

> And hackbench takes ages, already without running cyclictest:
> 
>   bash-3.00# time ./hackbench 10
>   Time: 83.157
>   real    1m23.935s
>   user    0m5.692s
>   sys     1m18.240s
> 
> With a standard non-rt kernel it just takes 10 seconds.
> 
>   bash-3.00# time ./hackbench 10
>   Time: 9.690
>   real    0m10.343s
>   user    0m0.404s
>   sys     0m9.928s
> 
> Is this the normal/expected behavior under -rt?

I've no idea where it comes from.

Robert
-- 
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