From owner-freebsd-fs@FreeBSD.ORG Wed Jun 20 16:39:44 2007 Return-Path: X-Original-To: freebsd-fs@freebsd.org Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 799A116A400 for ; Wed, 20 Jun 2007 16:39:44 +0000 (UTC) (envelope-from SRS0=5IyI=LU=ira.uka.de=esk@srs.kundenserver.de) Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.126.174]) by mx1.freebsd.org (Postfix) with ESMTP id 10EB113C489 for ; Wed, 20 Jun 2007 16:39:43 +0000 (UTC) (envelope-from SRS0=5IyI=LU=ira.uka.de=esk@srs.kundenserver.de) Received: from [213.144.1.98] (helo=localhost) by mrelayeu.kundenserver.de (node=mrelayeu3) with ESMTP (Nemesis), id 0MKxQS-1I131J36fc-0008Dr; Wed, 20 Jun 2007 18:27:02 +0200 From: Espen Skoglund MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <18041.21810.297355.202403@gargle.gargle.HOWL> Date: Wed, 20 Jun 2007 18:26:26 +0200 To: freebsd-fs@freebsd.org X-Mailer: VM 7.17 under 21.4 (patch 20) "Double Solitaire" XEmacs Lucid X-Provags-ID: V01U2FsdGVkX1+exciM/yYG1NK3DCPMjpptvWVnwdidZYAdRB0 aslh6W5NKdEl5gp5IaMIEM17L+uHoz9+44K9M76R4le/71s9m0 Qqgl9NV5e+sT23B9NA4AA== Subject: Snapshot usage guidelines (to avoid stability issues) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Jun 2007 16:39:44 -0000 Hi, A couple of days ago I decided to start using snapshots on my system. Knowing that the functionality has been available for quite some time now I (apparently wrongly) assumed that it was ready for production use. My bad. My system, a 6-STABLE from week and a half ago, uses two 250GB gstriped disks and has about 4-5 snapshots on one 215GB UFS partiton. This morning I learned that things had gone terribly wrong during some nightly cronjobs, hanging the whole system. Suspecting that snapshots were the culprit I soon learned after some investigation that the snapshot functionality wasn't nearly as stable as I had hoped for. Looking at PRs and mailing lists there seems to be mainly two outstanding stability issues with snapshots: a) snapshotted fs running full, and b) deleting large amount of files on an fs with multiple snapshots. The former issue, while certainly annoying, one could be able to work around. The latter issue, on the other hand, seems more like a definite show stopper. Am I right in inferring that the two above cases are main issues with snaphots at this time, or are there other known gotchas that I have to look out for. eSk