From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx3.redhat.com (mx3.redhat.com [172.16.48.32]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id i9SKLKr11446 for ; Thu, 28 Oct 2004 16:21:20 -0400 Received: from main.gmane.org (main.gmane.org [80.91.229.2]) by mx3.redhat.com (8.12.11/8.12.11) with ESMTP id i9SKL9mC003626 for ; Thu, 28 Oct 2004 16:21:09 -0400 Received: from root by main.gmane.org with local (Exim 3.35 #1 (Debian)) id 1CNGlg-0007No-00 for ; Thu, 28 Oct 2004 22:21:08 +0200 Received: from triangulo.it.uc3m.es ([163.117.139.109]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 28 Oct 2004 22:21:08 +0200 Received: from ptb by triangulo.it.uc3m.es with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 28 Oct 2004 22:21:08 +0200 From: Peter T. Breuer Date: Thu, 28 Oct 2004 21:17:11 +0200 Message-ID: References: <41801ADE.6030308@monjoin.net> <20041028011738.GD13737@kluge.net> <41808B37.40406@monjoin.net> <20041028063530.GA13279@percy.comedia.it> Sender: news Subject: [linux-lvm] Re: Software raid on top of lvm logical volume Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-lvm@redhat.com Luca Berra wrote: > On Thu, Oct 28, 2004 at 08:01:27AM +0200, Eric Monjoin wrote: > >md9 : active raid1 emcpowerd1[2] [dev e8:e1][0] > > 42829184 blocks [2/1] [U_] > > [>....................] recovery = 1.4% (630168/42829184) > >finish=68.1min speed=10315K/sec > this is a problem with linux md raid. it does not support fast resync > with a bitmap of changed sectors, there is a project to implement it, > but it is not yet in the standard kernel. > look on the linux-raid mailing list archives for something called 'fast > raid 1'. fr1.sf.net (also fr5.sf.net may be of interest). and http://www.it.uc3m.es/ptb/fr1 (yes, I am the author). Those are for 2.4 kernels. A version fo fr1 for 2.6 kernels with additional ondisk bitmaps has been done by Paul Clements, the linux nbd maintainer, and patches by him are around. I should look them up and merge the two .. bids accepted! > i do not believe you would have any advantage in stacking md above lvm > anyway. That is right. In fact it sounds downright risky to me. Peter