From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Zarochentsev Subject: Re: How long will a shrinkfs take? Date: Fri, 11 Jun 2004 00:54:19 +0400 Message-ID: <20040610205419.GQ8091@backtop.namesys.com> References: <40C8C0EF.7060704@dgreaves.com> Mime-Version: 1.0 Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com Content-Disposition: inline In-Reply-To: <40C8C0EF.7060704@dgreaves.com> List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: David Greaves Cc: reiserfs-list@namesys.com On Thu, Jun 10, 2004 at 09:13:35PM +0100, David Greaves wrote: > Hi > > I have a 1Tb reiserfs that I want to shrink to 500Gb > 400Gb of data is used. > > Any estimates as to how long this will take? > Sustained I/O is about 33Mb/s at the fs level, 44 Mb/s at the lv level > and 65Mb/s at the md0 level. ReiserFs shrinker reads all tree nodes as fsck does (reiserfsck --check may be used for rough estimation) plus shrinker writes relocated nodes (this highly depends on how many nodes are above 500GB boundary). Anyway running reiserfsck --check before shrinking is a good practice. > > (I didn't expect the fs to be so slow so I'm going to try a few tuning > params on the new 500Gb space before copying over the data and growing > back to a Tb) > > Is it proportional to the amount of shrinkage (ie 2 hrs to reduce by > 50G, 20 hrs to reduce by 500Gb) > David -- Alex.