From owner-freebsd-hackers@FreeBSD.ORG Thu Jan 24 14:54:34 2013 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 0F4F2B98; Thu, 24 Jan 2013 14:54:34 +0000 (UTC) (envelope-from nowakpl@platinum.linux.pl) Received: from platinum.linux.pl (platinum.edu.pl [81.161.192.4]) by mx1.freebsd.org (Postfix) with ESMTP id BDC46CFF; Thu, 24 Jan 2013 14:54:33 +0000 (UTC) Received: by platinum.linux.pl (Postfix, from userid 87) id 1BF1147E11; Thu, 24 Jan 2013 15:54:32 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on platinum.linux.pl X-Spam-Level: X-Spam-Status: No, score=-1.4 required=3.0 tests=ALL_TRUSTED,AWL autolearn=disabled version=3.3.2 Received: from [10.255.0.2] (unknown [83.151.38.73]) by platinum.linux.pl (Postfix) with ESMTPA id C7BC447DE6; Thu, 24 Jan 2013 15:54:31 +0100 (CET) Message-ID: <51014B28.8070404@platinum.linux.pl> Date: Thu, 24 Jan 2013 15:54:32 +0100 From: Adam Nowacki User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130107 Thunderbird/17.0.2 MIME-Version: 1.0 To: Wojciech Puchar Subject: Re: ZFS regimen: scrub, scrub, scrub and scrub again. References: <20130122073641.GH30633@server.rulingia.com> <51013345.8010701@platinum.linux.pl> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-fs@freebsd.org, freebsd-hackers@freebsd.org X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Jan 2013 14:54:34 -0000 On 2013-01-24 15:24, Wojciech Puchar wrote: >> For me the reliability ZFS offers is far more important than pure >> performance. > Except it is on paper reliability. This "on paper" reliability in practice saved a 20TB pool. See one of my previous emails. Any other filesystem or hardware/software raid without per-disk checksums would have failed. Silent corruption of non-important files would be the best case, complete filesystem death by important metadata corruption as the worst case. I've been using ZFS for 3 years in many systems. Biggest one has 44 disks and 4 ZFS pools - this one survived SAS expander disconnects, a few kernel panics and countless power failures (UPS only holds for a few hours). So far I've not lost a single ZFS pool or any data stored.