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Date: Mon, 12 Jul 2004 03:44:42 -0700
From: William Lee Irwin III <wli@holomorphy.com>
To: Rajput <rajput@indo.net>
Cc: Con Kolivas <kernel@kolivas.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Instrumenting high latency
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On Mon, Jul 12, 2004 at 04:11:32PM +0530, Rajput wrote:
> what is the difference in interrupt latency with and without your patch.
> Regards,
> Rajput.

This is meant to instrument scheduling latency, it doesn't improve
anything directly. It likely introduces a fair amount of overhead.
In the event a poor preempt_thresh= parameter is chosen, it may render
systems effectively unusable due to endless printk()'ing (which I should
fix via printk_ratelimit() shortly).

I recommend applying and/or enabling this only for diagnostic purposes.


-- wli