From owner-freebsd-questions@FreeBSD.ORG Thu Jun 21 16:02:58 2012 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 69B74106566B for ; Thu, 21 Jun 2012 16:02:58 +0000 (UTC) (envelope-from mgamsjager@gmail.com) Received: from mail-wi0-f178.google.com (mail-wi0-f178.google.com [209.85.212.178]) by mx1.freebsd.org (Postfix) with ESMTP id 815C88FC0C for ; Thu, 21 Jun 2012 16:02:57 +0000 (UTC) Received: by wibhn6 with SMTP id hn6so647546wib.13 for ; Thu, 21 Jun 2012 09:02:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:references:from:content-type:x-mailer:in-reply-to :message-id:date:cc:content-transfer-encoding:mime-version; bh=zbntv4M9dZ/P47E28eQXlBV3cawfA6rX13YKI/oRy70=; b=Is4WyIRtgrkntfmt8XqfkZJ4V2NqMJR6FZ5EgeZAOcCcGauH8dOB+8DzyGcENY99lP phsGwL2bhtrHl6syCGshrS+C7yCYXWzU2U27BT8qfSvdeybFrsYNzRe1FwNh9WRm0aXY qlNnTI4GRyL3csq4AxThCC54g0l/2y1L1vbRNr3zWMvbiS/tjX/UVfZvQ/pdWCkwOxs+ NlJyVxcrJM73XlsfezVIFxB8oWa6FPKsNv/gyr/xSDikihuRWUoF88g0Q/udlpmKA4bs RjyXt/OXtLHpXtYKIhp3tyoqpEJFNuXwHs+eFOvO2NT6CzLnBBrzrq+tx7aHtMmJs1EZ H0ZA== Received: by 10.216.213.143 with SMTP id a15mr16240393wep.156.1340294576193; Thu, 21 Jun 2012 09:02:56 -0700 (PDT) Received: from [192.168.2.7] (5ED03002.cm-7-1a.dynamic.ziggo.nl. [94.208.48.2]) by mx.google.com with ESMTPS id d3sm90187659wiz.9.2012.06.21.09.02.54 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 21 Jun 2012 09:02:55 -0700 (PDT) References: <4FE2CE38.9000100@gmail.com> From: Matthias Gamsjager Content-Type: text/plain; charset=us-ascii X-Mailer: iPad Mail (9B176) In-Reply-To: Message-Id: Date: Thu, 21 Jun 2012 18:02:52 +0200 Cc: FreeBSD Questions Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (1.0) Subject: Re: Is ZFS production ready? 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: Thu, 21 Jun 2012 16:02:58 -0000 On 21 jun. 2012, at 17:15, Wojciech Puchar w= rote: >>=20 >> I do understand your setup but I dont have too agree that it is a good >=20 > so i would repeat my question. > Assume you have 48 disks, in mirrored configuration (24 mirrors) and 480 u= sers with their data on them. >=20 > Your solution with ZFS - ZFS crashes or you get double disk failure. > Assuming the latter by average one per 24 file (randomly chosen) is destro= yed which - in practice and limited time, means everything destroyed. Actual= ly more than one per 24 - large files can be spread over. >=20 > Your solution with UFS - better as there is fsck which slowly but successf= ully repairs problem. with double disk failure - the same! >=20 >=20 > You restore everything from backup (i assume you have one). This takes lik= e a day or more, one or two complete work days lost+all users in practice lo= st everything since last backup. >=20 > My solution with UFS - fsck in case of failure work in parallel on 24 disk= s so not that long. double disk failure means losing data of 1/24 users. >=20 > every one per 24 user cannot work, others work and i without any stress do= recover this 1/24 of users data from backup after putting replacement disks= . >=20 > 1/24 of users lost data since last backup, and some hours of time. >=20 >=20 > Even assuming ZFS is perfect then we both have problems as often, but my p= roblems are 1/24 as severe as yours. >=20 >=20 > Just don't ask me for help when unhappy users will want to cut off your he= ad. >=20 >>> And you've never seen me, yet i still exist. >>>=20 >>=20 >> Really? that's you anwser to my question. The most childish answer I coul= d >=20 > stupid answer to stupid question. > You never seen - but they do happens. In other topic you hammerd on fact and if someone ask you to deliver them i= ts a stupid question.=20 And about the dram error. I really hope you do use ecc memory in production w= hich renders your scenario invalide. And even then its a claim made by you s= ome random dude on a list.=20 Without proper test scenario and documentation such claims are just useless.= =20 And a proper layout zfs will withstand a double disk failure with zero downt= ime...where younhave to tell your customer they just lost a day work=