Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751345AbWEICCZ (ORCPT ); Mon, 8 May 2006 22:02:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751346AbWEICCZ (ORCPT ); Mon, 8 May 2006 22:02:25 -0400 Received: from dvhart.com ([64.146.134.43]:25058 "EHLO dvhart.com") by vger.kernel.org with ESMTP id S1751345AbWEICCZ (ORCPT ); Mon, 8 May 2006 22:02:25 -0400 Message-ID: <445FF82A.2080106@mbligh.org> Date: Mon, 08 May 2006 19:02:18 -0700 From: Martin Bligh User-Agent: Mozilla Thunderbird 1.0.7 (X11/20051011) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Nick Piggin Cc: Arjan van de Ven , Erik Mouw , Andrew Morton , Jason Schoonover , linux-kernel@vger.kernel.org Subject: Re: High load average on disk I/O on 2.6.17-rc3 References: <200605051010.19725.jasons@pioneer-pra.com> <20060507095039.089ad37c.akpm@osdl.org> <445F548A.703@mbligh.org> <1147100149.2888.37.camel@laptopd505.fenrus.org> <20060508152255.GF1875@harddisk-recovery.com> <1147102290.2888.41.camel@laptopd505.fenrus.org> <445FF714.4050803@yahoo.com.au> In-Reply-To: <445FF714.4050803@yahoo.com.au> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 973 Lines: 27 Nick Piggin wrote: > Arjan van de Ven wrote: > >>> ... except that any kernel < 2.6 didn't account tasks waiting for disk >>> IO. >>> >> >> they did. It was "D" state, which counted into load average. >> > > Perhaps kernel threads in D state should not contribute toward load avg. > > Userspace does not care whether there are 2 or 20 pdflush threads waiting > for IO. However, when the network/disks can no longer keep up, userspace > processes will end up going to sleep in writeback or reclaim -- *that* is > when we start feeling the load. Personally I'd be far happier having separated counters for both. Then we can see what the real bottleneck is. Whilst we're at it, on a per-cpu and per-elevator-queue basis ;-) M. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/