From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id A29B47F3F for ; Wed, 14 Jan 2015 00:07:28 -0600 (CST) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay1.corp.sgi.com (Postfix) with ESMTP id 812708F8050 for ; Tue, 13 Jan 2015 22:07:25 -0800 (PST) Received: from smtp.welcomes-you.com (welcomes-you.com [144.76.218.113]) by cuda.sgi.com with ESMTP id 5wJWK7b9F01PABIP for ; Tue, 13 Jan 2015 22:07:18 -0800 (PST) Message-ID: <54B60784.5090505@aei.mpg.de> Date: Wed, 14 Jan 2015 07:07:00 +0100 From: Carsten Aulbert MIME-Version: 1.0 Subject: Re: extremely slow file creation/deletion after xfs ran full References: <54B387A1.6000807@aei.mpg.de> <54B3CC6A.4080405@aei.mpg.de> <20150112155206.GD25944@bfoster.bfoster> <54B3F19D.6030307@aei.mpg.de> <20150112163749.GE25944@bfoster.bfoster> <54B40552.50106@aei.mpg.de> <54B57ACD.60600@hardwarefreak.com> <54B57C59.9070207@aei.mpg.de> <54B58367.1070008@hardwarefreak.com> In-Reply-To: <54B58367.1070008@hardwarefreak.com> 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 Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Stan Hoeppner Cc: xfs@oss.sgi.com Hi Stan On 01/13/2015 09:43 PM, Stan Hoeppner wrote: > With your file sizes that seems a recipe for hotspots. What do the > controller metrics tell you about IOs per drive, bytes per drive? Are > they balanced? > They looked ok from 10000ft, but unfortunately, the controller is not that talkative :( >> After the arrival of "advanced format" HDD and SSDs we usually try to >> align everything to full 1 MByte or larger, just to be sure any >> combination of 512b, 4kb, ... will eventually align :) > > It's not that simple with striping. Partitions need to start and end on > stripe boundaries, not simply multiples of 4KB or 1MB as with single > disks. If you use non power of 2 drive counts in a stripe, aligning at > multiples of 1MB will screw ya, e.g. 12 drives * 64KB is a 768KB stripe. At the moment there are 16 disks (or 8 "data" disks), so here, power of 2 still prevails. But still, very valid remark! Cheers Carsten _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs