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 BB06D138350 for ; Sun, 3 May 2020 21:32:39 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id CD61BE09D0; Sun, 3 May 2020 21:32:34 +0000 (UTC) Received: from smtp.hosts.co.uk (smtp.hosts.co.uk [85.233.160.19]) (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 827E0E094B for ; Sun, 3 May 2020 21:32:31 +0000 (UTC) Received: from [81.153.126.158] (helo=[192.168.1.225]) by smtp.hosts.co.uk with esmtpa (Exim) (envelope-from ) id 1jVMDt-000ALm-7x for gentoo-user@lists.gentoo.org; Sun, 03 May 2020 22:32:29 +0100 Subject: Re: [gentoo-user] which linux RAID setup to choose? To: gentoo-user@lists.gentoo.org References: From: antlists Message-ID: Date: Sun, 3 May 2020 22:32:32 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 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 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit X-Archives-Salt: f531c49f-6c19-43da-83b5-9638337fc0e4 X-Archives-Hash: 0f4cf28573e84313a220dafcb3b22bc4 On 03/05/2020 21:07, Rich Freeman wrote: > I don't think you should focus so much on whether read=write in your > RAID. I'd focus more on whether read and write both meet your > requirements. If you think about it, it's obvious that raid-1 will read faster than it writes - it has to write two copies while it only reads one. Likewise, raids 5 and 6 will be slower writing than reading - for a normal read it only reads the data disks, but when writing it has to write (and calculate!) parity as well. A raid 1 should read data faster than a lone disk. A raid 5 or 6 should read noticeably faster because it's reading across more than one disk. If you're worried about write speeds, add a cache. Cheers, Wol