From: SandeepKsinha Subject: Re: Question about ext4 online defrag test case Date: Fri, 15 Jan 2010 19:11:28 +0530 Message-ID: <37d33d831001150541o1b674580u14719e72e3ad8e78@mail.gmail.com> References: <4B4EEF94.5000902@rs.jp.nec.com> <87f94c371001141304n18bcd208kd97f08646d37d1e2@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Akira Fujita , Theodore Tso , ext4 development To: Greg Freemyer Return-path: Received: from mail-bw0-f227.google.com ([209.85.218.227]:38481 "EHLO mail-bw0-f227.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753641Ab0AONla convert rfc822-to-8bit (ORCPT ); Fri, 15 Jan 2010 08:41:30 -0500 Received: by bwz27 with SMTP id 27so546232bwz.21 for ; Fri, 15 Jan 2010 05:41:28 -0800 (PST) In-Reply-To: <87f94c371001141304n18bcd208kd97f08646d37d1e2@mail.gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Fri, Jan 15, 2010 at 2:34 AM, Greg Freemyer wrote: > On Thu, Jan 14, 2010 at 5:19 AM, Akira Fujita wrote: >> Hi Ted, >> >>> E2defrag should hopefully be releasable in Karmic+1. >>> There are still a lot of bugs that are still being fixed in the def= rag >>> code, >>> some of which could cause data loss. They work fine >>> if the system isn't under stress, sure, but acid test is to make su= re >>> things work OK even when the system is under memory pressure and >>> swapping heavily, or when the file is being actively modified at th= e point >>> where the defrag takes place. >> >> I found your comment about ext4 online defrag on Ubuntu BBS by accid= ent. >> https://bugs.launchpad.net/ubuntu/+source/e2fsprogs/+bug/321528 >> >> I would like to address this problem so I ran e4defrag on the system >> which was under memory pressure. But unfortunately I could not find = the bug. >> If you have already known how to reproduce this kind of problem, >> could you teach me how? >> >> Regards, >> Akira Fujita > > Sandeep, I've added you and I to this thread since oshm is using the > same ext4_move_extents ioctl as E2defrag. > > Also, the above highlights the need for us to test ohsm relocates wit= h > data updates in progress. =A0Also with memory pressure which I had no= t > really thought about before. > We have been testing ext4_move_extent through OHSM relocation till now. Also, we have been testing it on real-world data (http://edrm.net/activities/projects/data-set). But yes we surely need to test then on a system under memory pressure. > We can discuss that on the ohsm list if needed. > > Greg > --=20 Regards, Sandeep OHSM Team https://sourceforge.net/projects/ohsm/ =93To learn is to change. Education is a process that changes the learn= er.=94 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html