Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755256AbZJPT26 (ORCPT ); Fri, 16 Oct 2009 15:28:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754558AbZJPT25 (ORCPT ); Fri, 16 Oct 2009 15:28:57 -0400 Received: from mail.lang.hm ([64.81.33.126]:45956 "EHLO bifrost.lang.hm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753224AbZJPT25 (ORCPT ); Fri, 16 Oct 2009 15:28:57 -0400 Date: Fri, 16 Oct 2009 12:28:49 -0700 (PDT) From: david@lang.hm X-X-Sender: dlang@asgard.lang.hm To: Holger Kiehl cc: Justin Piszcz , linux-raid , linux-kernel Subject: Re: Raid reconstructing and process hanging in D state In-Reply-To: Message-ID: References: User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1678 Lines: 42 On Fri, 16 Oct 2009, Holger Kiehl wrote: > On Fri, 16 Oct 2009, Justin Piszcz wrote: >> Hi, >> >> I have the same problem with mdadm/raid-1, if you do not limit the speed in >> the speed_limit_min paramter, it will starve the I/O from all other >> processes and result in the same problem you are having. >> > But in my case speed_limit_min was set to 1000 and speed_limit_max was 200000 > (ie. the default) and this still caused all process to hang in D-state. Only > lowering speed_limit_max helped to make the system responsive again. yep, MD raid will use every bit of disk bandwidth there is. even worse, the speed_limit_* appears to be per-drive, not per array (although the /proc/mdstat info is per array), so if you have lots of drives on one controller card it will kill the system and still think that it's not maxed out. I did a 45 disk array hooked into two PCI slots and found that I needed to set speed_limit_max _very_ low to avoid this sort of problem. David Lang >> But for me I'm not sure about the reconstruction-- this happens for me >> during a raid verify/check. >> > This was also the case for me, during a raid verify/check. > > Holger > -- > 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/ > -- 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/