From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8C5EC352A1 for ; Sat, 3 Dec 2022 05:45:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230010AbiLCFpc (ORCPT ); Sat, 3 Dec 2022 00:45:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229458AbiLCFpb (ORCPT ); Sat, 3 Dec 2022 00:45:31 -0500 Received: from www18.qth.com (www18.qth.com [69.16.238.59]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1EBAACA62 for ; Fri, 2 Dec 2022 21:45:30 -0800 (PST) Received: from [73.207.192.158] (port=34138 helo=jpo) by www18.qth.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1p1LL7-0005t4-MF for linux-raid@vger.kernel.org; Fri, 02 Dec 2022 23:45:29 -0600 Date: Sat, 3 Dec 2022 05:45:28 +0000 From: David T-G To: Linux RAID list Subject: Re: about linear and about RAID10 Message-ID: <20221203054528.GR19721@jpo> Reply-To: Linux RAID list References: <20221123220736.GD19721@jpo> <20221124032821.628cd042@nvm> <20221124211019.GE19721@jpo> <512a4cdd-9013-e158-7c77-7409cd0dc3a1@youngman.org.uk> <20221125133050.GH19721@jpo> <20221128144630.GN19721@jpo> <548f5325-0c3b-1642-2b08-ae7b637b3ad3@thelounge.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <548f5325-0c3b-1642-2b08-ae7b637b3ad3@thelounge.net> User-Agent: Mutt/1.10.1 (2018-07-13) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - www18.qth.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - justpickone.org X-Get-Message-Sender-Via: www18.qth.com: authenticated_id: dmail@justpickone.org X-Authenticated-Sender: www18.qth.com: dmail@justpickone.org X-Source: X-Source-Args: X-Source-Dir: Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org Reindl, et al -- ...and then Reindl Harald said... % % Am 28.11.22 um 15:46 schrieb David T-G: % > I don't at this time have a device free to plug in locally to back up the % > volume to destroy and rebuild as linear, so that will have to wait. When % > I do get that chance, though, will that help me get to the awesome goal % > of actually INCREASING performance by including a RAID0 layer? % % stacking layers over layers will *never* increase performance - a pure RAID0 % will but if one disk is dead all is lost True, and we definitely don't want that. % % additional RAID0 on top or below another RAID won't help I could believe that, because what I don't know about RAID would fill a book, but I thought that the idea of RAID10 speeding up access was that the first half of the data is on the FIRST half of the /first/ disk and the second half of the data is on the FIRST half of the /second/ disk and so the heads only move over half the disk for reads. % % your main problem starts by slicing your drives in dozens of partitions and % "the idea being that each piece of which should take less time to rebuild if % something fails" [snip] Whoops! You're on the wrong machine. This one mirrors two disks; that one is the one that has a bunch. HANN :-D -- David T-G See http://justpickone.org/davidtg/email/ See http://justpickone.org/davidtg/tofu.txt