From owner-freebsd-hackers Thu Apr 8 2:57:53 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from rt2.synx.com (tech.boostworks.com [194.167.81.239]) by hub.freebsd.org (Postfix) with ESMTP id AD67B14D66 for ; Thu, 8 Apr 1999 02:57:45 -0700 (PDT) (envelope-from root@synx.com) Received: from synx.com (rn.synx.com [192.1.1.241]) by rt2.synx.com (8.9.1/8.9.1) with ESMTP id LAA08304; Thu, 8 Apr 1999 11:55:26 +0200 (CEST) Message-Id: <199904080955.LAA08304@rt2.synx.com> Date: Thu, 8 Apr 1999 11:55:23 +0200 (CEST) From: Remy Nonnenmacher Reply-To: remy@synx.com Subject: Re: Volume managers (was: Separate boot partition?) To: grog@lemis.com Cc: hackers@FreeBSD.ORG In-Reply-To: <19990408182917.G2142@lemis.com> MIME-Version: 1.0 Content-Type: TEXT/plain; CHARSET=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On 8 Apr, Greg Lehey wrote: > On Thursday, 8 April 1999 at 10:44:15 +0200, Remy Nonnenmacher wrote: >> On 8 Apr, Greg Lehey wrote: >>> On Thursday, 8 April 1999 at 8:52:24 +0100, Dom Mitchell wrote: >>>> On 8 April 1999, Greg Lehey proclaimed: >>>>> I can't see why not, since it's possible now. What we still need to >>>>> do is find a way to extend a file system, but that's a ufs issue >>>>> (which has a solution), not a volume manager issue. >>>> >>>> What about shrinking an fs? Is that feasible? Possible? >>> >>> According to Kirk McKusick, no. >>> >> too bad !! >> >> Really, merging the best of all worlds (AIX PV migration, fs 'live' >> extendability) *AND* fs shrinking would be a really impressive >> performance. >> >> Think about it : A set of SCA, hot-pluggable disks. Every fs movable, >> resizable (up/down), every disk content movable from/to every other >> one.... the perfect power-on once, run till-end-of-universe server. > > Well, with the exception of the file system shrinking, we have all > that. I honestly don't think we'll find a need to shrink file systems > too often. > Sure, but 'not too often' is not 'never' and when case raises, for exemple with these messages : (assuming you can't hot-add disks...) - "too bad: you are 100MB too short on this fs. 200MB are wasted here and here. watch and cry!!" - "Ha Ha !! 100MB needed for install, 50 MB available. Anyway, have a look around there: 10 fs with 50MB wasted on each one!!" The main problem is that you need to plan a shutdown and a time-costly work (nightly ;). BTW, a workaround (with spares) would be to be able to create a new, downsized, fs and then migrate content of the old one to the new one. Steps something like : - Have everybody using the old one freeze (hands up!) - sync the old fs - Move the content of the old fs - alias old->new - Everybody warm. - free space owned by the old fs. Feasible ? (ANW, would be helpfull sometime to freeze every process using a fs...) RN. IaM To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message