From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754127AbYJGKaA (ORCPT ); Tue, 7 Oct 2008 06:30:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753272AbYJGK3n (ORCPT ); Tue, 7 Oct 2008 06:29:43 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:39940 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753224AbYJGK3m (ORCPT ); Tue, 7 Oct 2008 06:29:42 -0400 Subject: Re: IRQ balancing on a router From: Peter Zijlstra To: Arjan van de Ven Cc: Jan Kasprzak , linux-kernel@vger.kernel.org In-Reply-To: <20081003063857.76b7b61a@linux.intel.com> References: <20081003132117.GM16624@fi.muni.cz> <20081003063857.76b7b61a@linux.intel.com> Content-Type: text/plain Date: Tue, 07 Oct 2008 12:29:39 +0200 Message-Id: <1223375380.26330.24.camel@lappy.programming.kicks-ass.net> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2008-10-03 at 06:38 -0700, Arjan van de Ven wrote: > The good news is that irqthreads at least have the potential to solve > this "lack of information"; if not, we could consider doing a form of > microaccounting for irq handlers.... I have some patches floating about that account for nmi/irq/softirq time in a fine grained scale. The trouble is that i've so far not found a way to handle the case of a jiffie based sched_clock(). The trouble with that is that time always increases in IRQ context, so nmi=0, softirq=0, regular=0 but irq=100%, which is obviuosly sub-optimal :-)