From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id p53069Fk232003 for ; Thu, 2 Jun 2011 19:06:09 -0500 Received: from mail-px0-f174.google.com (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id F1FEB49968E for ; Thu, 2 Jun 2011 17:06:08 -0700 (PDT) Received: from mail-px0-f174.google.com (mail-px0-f174.google.com [209.85.212.174]) by cuda.sgi.com with ESMTP id 36Cgm6jJf8ypFULg for ; Thu, 02 Jun 2011 17:06:08 -0700 (PDT) Received: by pxi15 with SMTP id 15so911270pxi.5 for ; Thu, 02 Jun 2011 17:06:08 -0700 (PDT) Message-ID: <4DE8256C.10706@philkarn.net> Date: Thu, 02 Jun 2011 17:06:04 -0700 From: Phil Karn MIME-Version: 1.0 Subject: Re: I/O hang, possibly XFS, possibly general References: <19943.56524.969126.59978@tree.ty.sabi.co.UK> In-Reply-To: <19943.56524.969126.59978@tree.ty.sabi.co.UK> 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: Peter Grandi Cc: Linux fs XFS On 6/2/11 11:56 AM, Peter Grandi wrote: > Disclaimer: some smart people I know built knowingly a similar > and fortunately much smaller collection of RAID6 sets because > that was the least worst option for them, and since they know > that it will not fill up before they can replace it, they are > effectively short-stroking all those 2TB drives (I still would > have bought ERC ones if possible) so it's cooler than it looks. What do you mean by "short stroking"? That the data (and head motions) stay in one part of the disk? I haven't been using XFS that long and I'm no expert on it, but I've noticed that it seems to distribute files pretty evenly across an entire disk. Even without the inode64 option, only the inodes are kept at the beginning; the data can be anywhere. The only way I can think of to confine the activity on a lightly-loaded XFS file system to one part of a disk (e.g., to reduce average seek times and to stay in the faster outer area of the drive) is to create partitions that initially span only part of the disk, then grow them later as needed. Is that what you mean? _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs