From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail05.adl6.internode.on.net ([150.101.137.143]:2297 "EHLO ipmail05.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752274AbdHTCEl (ORCPT ); Sat, 19 Aug 2017 22:04:41 -0400 Date: Sun, 20 Aug 2017 12:04:38 +1000 From: Dave Chinner Subject: Re: Estimate xfs_repair run time Message-ID: <20170820020438.GQ10621@dastard> References: <22ed5cf73260ae39bf59779b302d8ad3@assyoma.it> <20170819154804.GS4796@magnolia> <3fcdaa5ea4365a1ddb7c76070236e6b3@assyoma.it> <20170819162025.GT4796@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Gionatan Danti Cc: "Darrick J. Wong" , linux-xfs@vger.kernel.org On Sat, Aug 19, 2017 at 06:39:58PM +0200, Gionatan Danti wrote: > >{yes, yes, depends on which spindle(s) metadata end up on and how many > >files cross AGs} in that order. :) > > Mmm ok, as expected :) > Do you have any direct experience of xfs_repair run times on big and > full XFS filesystems? Yes. And there's no hard and fast number we can give you because runtime will depends on the amount and density of the metadata, the speed of the underlying storage, how much RAM you have and how badly corrupted the filesystem is. IOWs, runtime can vary from a few minutes to a few days as you vary those parameters, and there's really no way to tell in advance where in that massive variance any specific production filesystem will land. Doing a test run (xfs_repair -n) to get a ballpark figure during a planned downtime period is the only way you'll get any idea of the *best case* repair duration on a *clean* filesystem. But the moment repair finds corruptions, all guesses you can make about runtime go out the window... Cheers, Dave. -- Dave Chinner david@fromorbit.com