From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id qAN2sMxX015418 for ; Thu, 22 Nov 2012 20:54:22 -0600 Received: from ipmail06.adl2.internode.on.net (ipmail06.adl2.internode.on.net [150.101.137.129]) by cuda.sgi.com with ESMTP id cqvGz3XWOdYwyb5t for ; Thu, 22 Nov 2012 18:56:33 -0800 (PST) Date: Fri, 23 Nov 2012 13:56:24 +1100 From: Dave Chinner Subject: Re: high load and xfsaild in d Message-ID: <20121123025624.GC32450@dastard> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Keith Keller Cc: linux-xfs@oss.sgi.com On Thu, Nov 22, 2012 at 06:13:48PM -0800, Keith Keller wrote: > Hello all, > > I recently deployed a new CentOS 6.3 file server, and soon after I > noticed that the load was consistenly at around 4, even with no obvious > activity. After checking around a bit, the only unusual thing I could > find is that the xfsaild threads are all consistently in D state: > > root 1744 0.0 0.0 0 0 ? D Nov16 7:46 [xfsaild/dm-2] > root 1756 0.0 0.0 0 0 ? D Nov16 7:44 [xfsaild/dm-1] > root 1759 0.0 0.0 0 0 ? D Nov16 7:57 [xfsaild/dm-3] > root 1762 0.0 0.0 0 0 ? D Nov16 5:59 [xfsaild/dm-0] That's a side effect of a minimal set of bug fixes that were needed to avoid a load related log space hang. Those fixes disabled the aild idling logic so the aild acts as a watchdog, so they wake up every 50ms to check if there's anything to do. You'll find that 3.0.x stable kernels have the same behaviour. The aild idling logic was re-enabled in mainstream kernels after the root cause of the log space hangs was diagnosed and fixed, but I can't see it ever being re-enabled in a CentOS 6.3 kernel.... Cheers, Dave -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs