From: Sandon Van Ness Subject: Re: Is >16TB support considered stable? Date: Sat, 29 May 2010 13:40:12 -0700 Message-ID: <4C017BAC.2000000@van-ness.com> References: <4BFFF4D2.6020908@van-ness.com> <4C001BEC.9080906@redhat.com> <4C00804D.7010000@van-ness.com> <87ljb3gwee.fsf@willster.local.flamingspork.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: linux-ext4@vger.kernel.org Return-path: Received: from box.houkouonchi.jp ([208.97.140.21]:33454 "EHLO box.houkouonchi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756147Ab0E2UkX (ORCPT ); Sat, 29 May 2010 16:40:23 -0400 Received: from [127.0.0.1] (houkouonchi.dreamhost.com [127.0.0.1]) by box.houkouonchi.net (Postfix) with ESMTPA id 8F51B100E3 for ; Sat, 29 May 2010 13:40:22 -0700 (PDT) In-Reply-To: <87ljb3gwee.fsf@willster.local.flamingspork.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 05/28/2010 09:32 PM, Stewart Smith wrote: > On Fri, 28 May 2010 19:47:41 -0700, Sandon Van Ness wrote: > >> able to allocate blocks or memory (it was a while back so I forget). I >> spent 24 hours defraging it getting the fragmentation down from like >> 99.9995% to 99.2% and the problem went away. XFS seems to excessively >> fragment (that horribly fragmented system was running mythtv and after >> switching to JFS I see way less fragmented files). >> > MythTV's IO path is well... hacked to get around all of ext3's quirks. > > You can: > - mount XFS with allocsize=64m (or similar) > - possibly use the XFS filestreams allocator > - comment out the fsync() in the mythtv tree > - LD_PRELOAD libeatmydata for myth. > > it turns out that writing a rather small amount of data and fsync()ing > (and repeating 1,000,000 times) makes the allocator cry a bit with > default settings. Especially if you were recording a few things at once. > Well JFS has absolutely no problems with files created via mythtv. I also am not going to be using mythtv on this system at all and I was just giving some examples of my past experience with XFS and why I will never use it. Anyway please no more XFS discussion or suggestions for other file-systems I was mainly curious on what the stability or peoples experiences are with ext4 and 64-bit addressing. I have long since decided I will never run XFS again as I can't ever trust it with my data again. I mainly wrote this list to try to find out what the opinions were on ext4 with >16 TiB file-systems.