From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: NOHZ: local_softirq_pending
Date: Thu, 18 Jun 2009 00:03:32 +0200 (CEST)
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Cc: linux-rt-users <linux-rt-users@vger.kernel.org>,
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	"'Rodrigo Partearroyo'" <rpartearroyo@albentia.com>
To: Iratxo Pichel Ortiz <ipichel@albentia.com>
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On Tue, 16 Jun 2009, Iratxo Pichel Ortiz wrote:
> I have tried disabling the CONFIG_NOHZ kernel option. Of course the trace is
> gone, but the weird behavior is still there. When I run my software without
> load from the network, the main task of the system experiences runtimes of
> about 700us. When I load the system, there are latencies of 50700us, so the
> 50ms delay is again there, and again the time when the task finishes is always
> X.296, 1 jiffy after the "NOHZ: pending..." was shown with CONFIG_NOHZ
> enabled.

What kind of system is this ? 

Can you please check whether you can reproduce with NOHZ=y and function
tracer enabled ?

That would be great.

Thanks,

	tglx