From owner-freebsd-questions@freebsd.org Thu Sep 10 12:57:56 2015 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 6E45BA01B88 for ; Thu, 10 Sep 2015 12:57:56 +0000 (UTC) (envelope-from paul@kraus-haus.org) Received: from mail-qg0-f49.google.com (mail-qg0-f49.google.com [209.85.192.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 2EB891B7F for ; Thu, 10 Sep 2015 12:57:55 +0000 (UTC) (envelope-from paul@kraus-haus.org) Received: by qgt47 with SMTP id 47so33961117qgt.2 for ; Thu, 10 Sep 2015 05:57:49 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:content-type:mime-version:subject:from :in-reply-to:date:content-transfer-encoding:message-id:references:to; bh=4ydx8s3CP3qRDU48YsW3phQV9UhpDIwCj6qpq2IGcuA=; b=fnx5PT3BbNiFUcQ5iCOQ2jmk7mzYeePb08WciCoUP/4HeTKI4GUPCH9TGg+LdmulDj JqXIJR7Qd7qGCbpZNJl5RDzr2gn+TOvyy+uDL3pJsTlSvCUu7mVMoc+ZrQfLcy2qIlok Wtzk1LfM0EnbeSkNY0lFZH2XiNas52NBJ0L4qI3y1XLYUAb99Gnrv9dxZJdZ2TyOi/Jt TYzv6XwS96XdS8oa5R5vbSJUWSOGqKfZTRbKiTij3nEUHm2dDgdCDNXKg9uV55VPCtgT xbY6zXeBxfM6ZYw6SbR6DTzGRPqsUCtfNI2Y9fZsmItaiossWoWbWoYQx/R7F8Ftd2zM yhKA== X-Gm-Message-State: ALoCoQnv6WqRyjJHHQlh2DfFXbJniU2/sYaay1BlHv/2ss7AXZ3Yx/oK7HTGg5VBlWLCT2CM8i2u X-Received: by 10.140.233.210 with SMTP id e201mr56207959qhc.88.1441889869065; Thu, 10 Sep 2015 05:57:49 -0700 (PDT) Received: from mbp-1.thecreativeadvantage.com (mail.thecreativeadvantage.com. [96.236.20.34]) by smtp.gmail.com with ESMTPSA id l8sm5883276qge.31.2015.09.10.05.57.46 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 10 Sep 2015 05:57:46 -0700 (PDT) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: Storage question From: Paul Kraus In-Reply-To: <55F10715.3040508@sneakertech.com> Date: Thu, 10 Sep 2015 08:57:44 -0400 Content-Transfer-Encoding: quoted-printable Message-Id: <4E5C9688-700F-460D-907C-0EE2DB65CE08@kraus-haus.org> References: <55EF3D23.5060009@hiwaay.net> <20150908220639.20412cbd@gumby.homeunix.com> <55EF5409.8020007@yahoo.com> <55EFC2DA.3020101@hiwaay.net> <5EB5C2C2-575B-40BD-BF6A-85F396C058FE@kraus-haus.org> <55F058FC.6080204@hiwaay.net> <55F09924.2000007@hiwaay.net> <67BE98EB-AD0F-46C2-AF26-02C65D828DCF@kraus-haus.org> <55F105B2.2080806@sneakertech.com> <55F10715.3040508@sneakertech.com> To: FreeBSD Questions X-Mailer: Apple Mail (2.1878.6) X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Sep 2015 12:57:56 -0000 On Sep 10, 2015, at 0:29, Quartz wrote: >>> Note also the =93dnr=94 datasets :-) >>=20 >> Btw, you seem to be going with the 'dummy dataset' method for = preventing >> fs fillup. What's the advantage of doing it this way vs = refreservation >> or any other method? >=20 > More specifically, dummy datasets strike me as kind of the ugly way of = handling this issue. Isn't it better to just set parameters on your real = datasets? I do it this way for two reasons. 1) Habit=85 I have been doing this since before zfs even had the = refreservation and refquota properties :-) I have been managing zfs in = production since zpool version 10 (clearly on Solaris since it has not = been ported anywhere else that early on). 2) Transparency=85 it is much easier to spot a =93dnr=94 dataset set = than realize that a refreservation is set on the base zpool/dataset. Note that if you use refreservation, you only need it on the top level = dataset in the zpool. -- Paul Kraus paul@kraus-haus.org