From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 6494F138350 for ; Mon, 4 May 2020 00:29:24 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 4C3CBE08F7; Mon, 4 May 2020 00:29:16 +0000 (UTC) Received: from mail-40138.protonmail.ch (mail-40138.protonmail.ch [185.70.40.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id E6FD0E05C1 for ; Mon, 4 May 2020 00:29:14 +0000 (UTC) Date: Mon, 04 May 2020 00:29:05 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail; t=1588552152; bh=Njb5DgXvDtQ+REDda6PwAEy7iecJdpOJgaZCaRdyb2c=; h=Date:To:From:Reply-To:Subject:In-Reply-To:References:From; b=yEd8yJ4oBlScxH905Uy6strhBeXsll09D2ura64VnzbaiaVN5EonGEgOJQXdIT7/2 4YGZaXbLw/aRZoRXMXFQEiywczkYZRvjPsuxgiZWSjlch14xk7kyBwMISUKXZdnkL9 1ZSkJKcfiZkGJXNR+kkRRvz5UyaSchmADMPa7zVw= To: "gentoo-user@lists.gentoo.org" From: Caveman Al Toraboran Subject: Re: [gentoo-user] which linux RAID setup to choose? Message-ID: <-7QyrJKV4ubMDjzMcpT1FGvMXuOHENcGFf_hPIS6UzXSdTh0R2nrHzrdPfeSnPMC6cM8GyzDf-sInOVupPDXOEItXUYRQkpa_ooQC2zXIfE=@protonmail.com> In-Reply-To: References: <2251dac1-92cd-7c3b-97ea-6a061fe01eb0@users.sourceforge.net> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org X-Auto-Response-Suppress: DR, RN, NRN, OOF, AutoReply MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-1.2 required=7.0 tests=ALL_TRUSTED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM shortcircuit=no autolearn=disabled version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on mail.protonmail.ch X-Archives-Salt: 4a7330f9-d49b-43bd-8ece-a9c3d7bddcf5 X-Archives-Hash: 77ef529055544cb5699ba9a430e32e04 On Monday, May 4, 2020 2:50 AM, hitachi303 wrote: > Am 03.05.2020 um 23:46 schrieb Caveman Al Toraboran: > > > so, in summary: > > /------------------------------------------------\ > > | a 5-disk RAID10 is better than a 6-disk RAID10 | > > | ONLY IF your data is WORTH LESS than 3,524.3 | > > | bucks. | > > \------------------------------------------------/ > > any thoughts? i'm a newbie. i wonder how > > industry people think? > > Don't forget that having more drives increases the odds of a failing > drive. If you have infinite drives at any given moment infinite drives > will fail. Anyway I wouldn't know how to calculate this. by drive, you mean a spinning hard disk? i'm not sure how "infinite" helps here even theoretically. e.g. say that every year, 76% of disks fail. in the limit as the number of disks approaches infinity, then 76% of infinity is infinity. but, how is this useful? > Most people are limited by money and space. Even if this isn't your > problem you will always need an additional backup strategy. The hole > system can fail. > I run a system with 8 drives where two can fail and they can be hot > swoped. This is a closed source SAS which I really like except the part > being closed source. I don't even know what kind of raid is used. > > The only person I know who is running a really huge raid ( I guess 2000+ > drives) is comfortable with some spare drives. His raid did fail an can > fail. Data will be lost. Everything important has to be stored at a > secondary location. But they are using the raid to store data for some > days or weeks when a server is calculating stuff. If the raid fails they > have to restart the program for the calculation. thanks a lot. highly appreciate these tips about how others run their storage. however, i am not sure what is the takeaway from this. e.g. your closed-source NAS vs. a large RAID. they don't seem to be mutually exclusive to me (both might be on RAID). to me, a NAS is just a computer with RAID. no? > Facebook used to store data which is sometimes accessed on raids. Since > they use energy they stored data which is nearly never accessed on blue > ray disks. I don't know if they still do. Reading is very slow if a > mechanical arm first needs to fetch a specific blue ray out of hundreds > and put in a disk reader but it is very energy efficient. interesting.