From owner-freebsd-questions@FreeBSD.ORG Wed Jan 21 04:41:22 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 181AC106566B for ; Wed, 21 Jan 2009 04:41:22 +0000 (UTC) (envelope-from gfritz@gmail.com) Received: from rv-out-0708.google.com (rv-out-0708.google.com [209.85.198.249]) by mx1.freebsd.org (Postfix) with ESMTP id D7BED8FC41 for ; Wed, 21 Jan 2009 04:41:21 +0000 (UTC) (envelope-from gfritz@gmail.com) Received: by rv-out-0708.google.com with SMTP id k29so4282253rvb.0 for ; Tue, 20 Jan 2009 20:41:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:received:date:from:to:cc :subject:message-id:references:mime-version:content-type :content-disposition:in-reply-to:user-agent; bh=UlxoiPDsOouFcR4PfauytGF7hMWRe4AiNcHgrcL6Xrg=; b=LWXi6s8c71VF29lmYHTacGJMjAG72XsM4VYuSceTi7mypOA/C8lTRdjUltAMlfjLZE SPeveFfAtfDkH7cdNt7Dl5yiz/f5VwMEu4QtfNIrMCrBShc3242OKkTxyPSAARGGTf/z V/FXqk5CC3b/VpQPEK/c94tf9DKUf96tSSh3Y= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=eXIiUxjw6AbRHfb1NnInMs/pLLgtkd39QK710asYdRYcE4N8pTiVLwGBgQJ99hBdkS 8mpgLJPcXcc0Xw8JThXF1p38JSdbquhx0u2FbcbUzPvW7ZSrF9nNzJNk+Ti/b9d1Nbp7 gSRr1KJRKlVEHwlSxDQG1flcE1uzfQL2PHZ/g= Received: by 10.140.177.15 with SMTP id z15mr866163rve.17.1232512880360; Tue, 20 Jan 2009 20:41:20 -0800 (PST) Received: from dev.null (231-175-174-206.cust.wirelessbeehive.com [206.174.175.231]) by mx.google.com with ESMTPS id k41sm5994754rvb.3.2009.01.20.20.41.19 (version=TLSv1/SSLv3 cipher=RC4-MD5); Tue, 20 Jan 2009 20:41:20 -0800 (PST) Received: by dev.null (Postfix, from userid 1002) id 7B5D4F4C; Tue, 20 Jan 2009 21:41:18 -0700 (MST) Date: Tue, 20 Jan 2009 21:41:18 -0700 From: Geoff Fritz To: Dan Nelson Message-ID: <20090121044118.GC30866@dev.null> References: <20090120235256.GB30866@dev.null> <20090121041747.GD45931@dan.emsphone.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090121041747.GD45931@dan.emsphone.com> User-Agent: Mutt/1.5.18 (2008-05-17) Cc: Geoff Fritz , freebsd-questions@freebsd.org Subject: Re: Way to prune/limit the ZFS zpool history? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Jan 2009 04:41:24 -0000 On Tue, Jan 20, 2009 at 10:17:47PM -0600, Dan Nelson wrote: > In the last episode (Jan 20), Geoff Fritz said: > > I've been experimenting with a series scripts that takes ZFS > > snapshots every minute, eventually destroying the oldest so that only > > so many remain available for a given window of time. > > > > This may seem a trivial concern with hard drive sizes being what they > > are these days, but after running a "zpool history" I started > > thinking that a ZFS create and destroy being performed every minute > > would add up to a lot over the course of a few years (current > > estimate is 62MB/year for the naming scheme of my snapshots). > > According to > http://docs.sun.com/app/docs/doc/819-5461/gdswe?l=en&a=view , the zpool > history file is between 128K and 32MB, depending on the size of the > pool. The FreeBSD import at > /sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_history.c agrees > with the docs :) I always forget that ZFS is documented on Sun's site as well as the man pages. Hopefully some day the FreeBSD docs will catch up w/ Sun's. Thanks a bunch for the pointer. Very informative. -- Geoff