From mboxrd@z Thu Jan 1 00:00:00 1970 From: kurt.van.dijck@eia.be (Kurt Van Dijck) Date: Wed, 9 Mar 2011 16:22:53 +0100 Subject: IRQ handler under load - slow response In-Reply-To: References: Message-ID: <20110309152252.GB333@e-circ.dyndns.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Mar 09, 2011 at 03:02:06PM +0100, Arno Steffen wrote: > ------------------ > > What have I done wrong? You put code with different scheduling needs in the same scheduling pool. > Do I have a chance to speed up the response > from changing inputs? I've been playing with scheduling policies before (I'm not the expert). My hint: your tasklet is executed in the softirq handler. This will run at normal priority (see '$ ps -jefHc' for example) a) You could 'chrt --rr PID' of your softirqd b) replace your tasklet with a threaded irq handler, which you can 'chrt --rr PID'. This has the effect that only your own piece of code is raised in priority. > > best regards > Steffen Hope this will help. Kurt