Re: High 50us+ latencies in the process signal handling path

["Luis Claudio R. Goncalves" <lclaudio@uudg.org>]

Ankita,

On Thu, Oct 18, 2007 at 06:56:14PM +0530, Ankita Garg wrote:
| Hi David,
| 
| On Thu, Oct 18, 2007 at 05:52:42AM -0700, David Miller wrote:
| > From: ankita@in.ibm.com (Ankita Garg)
| > Date: Thu, 18 Oct 2007 18:18:27 +0530
| > 
| > > Any thoughts on where in the code could these large latencies be
| > > attributed to?
| > 
| > If the max latency is usually the first one, it's could be the page
| > fault the signal handler is taking the first time it is executed.
| 
| Thanks for looking into this. Attaching the entire log from the testrun.
| It indicates that in each run of the 10000 iterations, there are about 100+
| failures, with large iterations. Also, on intrumenting the testcode to
| find out the iterations which see large latencies, I see that as the
| number of iterations increase, the latencies increase.

You might wanna check signaltest:

git clone git://git.kernel.org/pub/scm/linux/kernel/git/tglx/rt-tests.git rt-tests

Regards,
Luis
-- 
[ Luis Claudio R. Goncalves                    Bass - Gospel - RT ]
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