From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([59.151.112.132]:28800 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751586AbaGUB1O convert rfc822-to-8bit (ORCPT ); Sun, 20 Jul 2014 21:27:14 -0400 Message-ID: <53CC6B39.1060705@cn.fujitsu.com> Date: Mon, 21 Jul 2014 09:22:01 +0800 From: Wang Shilong MIME-Version: 1.0 To: TM , Subject: Re: 1 week to rebuid 4x 3TB raid10 is a long time! References: In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi, On 07/20/2014 04:45 PM, TM wrote: > Hi, > > I have a raid10 with 4x 3TB disks on a microserver > http://n40l.wikia.com/wiki/Base_Hardware_N54L , 8Gb RAM > > Recently one disk started to fail (smart errors), so I replaced it > Mounted as degraded, added new disk, removed old > Started yesterday > I am monitoring /var/log/messages and it seems it will take a long time > Started at about 8010631739392 > And 20 hours later I am at 6910631739392 > btrfs: relocating block group 6910631739392 flags 65 > > At this rate it will take a week to complete the raid rebuild!!! Just my two cents: Since 'btrfs replace' support RADI10, I suppose using replace operation is better than 'device removal and add'. Another Question is related to btrfs snapshot-aware balance. How many snapshots did you have in your system? Of course, During balance/resize/device removal operations, you could still snapshot, but fewer snapshots should speed things up! Anyway 'btrfs replace' is implemented more effective than 'device remova and add'.:-) Thanks, Wang > > Furthermore it seems that the operation is getting slower and slower > When the rebuild started I had a new message every half a minute, now it’s > getting to OneAndHalf minutes > Most files are small files like flac/jpeg > > One week for a raid10 rebuild 4x3TB drives is a very long time. > Any thoughts? > Can you share any statistics from your RAID10 rebuilds? > > If I shut down the system, before the rebuild, what is the proper procedure > to remount it? Again degraded? Or normally? Can the process of rebuilding > the raid continue after a reboot? Will it survive, and continue rebuilding? > > Thanks in advance > TM > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >