From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mr3.vodafonemail.de (mr3.vodafonemail.de [145.253.228.163]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1CCC61822CB for ; Wed, 12 Jun 2024 17:25:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=145.253.228.163 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718213147; cv=none; b=Trr4bT/UikUhNPvHa5YDud2jbRnOilWRPLVHN17fA1jpakSL7zByqr6eX9W/bY/YUPwmmyA7QcsUip5MGzkLCCWEuTTK7ydflpogV+b3MujAxAWlETUtG0INy9BxP5v4gEHA878uGL6Y60g/RtZ109r1kv99R5KbUYyoxPgKQjI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718213147; c=relaxed/simple; bh=DbJ5RfhaUXcy/D8y7fI32SmVxokGxUrzzGh0ZUknqsQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=k0RSpid6c5X6wRvGQqZVrZDTv1w9RO2zwHDSTwDJ/9g0M/CY08iKkF6DiMWYNiWhN4yEaJ6j21ACCwDJ1Z4lXjFZVyPWKHsYjrDQyhV2nbiwwdqNsBg57t71VCToUt53t4GFkFAfbIPAf9GzT0n3dEmgpXaIGXEdQrYaQWveAG8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=nexgo.de; spf=pass smtp.mailfrom=nexgo.de; dkim=pass (1024-bit key) header.d=nexgo.de header.i=@nexgo.de header.b=Nlu/VPYZ; arc=none smtp.client-ip=145.253.228.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=nexgo.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nexgo.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=nexgo.de header.i=@nexgo.de header.b="Nlu/VPYZ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nexgo.de; s=vfde-mb-mr2-23sep; t=1718213140; bh=8NtTW8vVZUWBJuTTl3M6x2VlPcflAivSzUYu8/fNBfc=; h=Date:From:To:Subject:Message-ID:References:Content-Type: In-Reply-To:From; b=Nlu/VPYZjSK1yQSlVpMjrb/6kLRSexvnEmkal3GhqNe4U6MNnh5pHDi7ZPbqqq0Ay 9HBla+Sr6eawg1BiPaLRcmJxSpbE2TWuJ9f3ih5TlfGJbIXbEL04H+pZum2UzkQXHj LTkI9/MBSPWnRgru0Vb79+sPSaV+nG4xLJ6RUq2U= Received: from smtp.vodafone.de (unknown [10.0.0.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by mr3.vodafonemail.de (Postfix) with ESMTPS id 4VzsrN4T9Rz1yXC; Wed, 12 Jun 2024 17:25:40 +0000 (UTC) Received: from lazy.lzy (p579d746a.dip0.t-ipconnect.de [87.157.116.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp.vodafone.de (Postfix) with ESMTPSA id 4Vzsr674CFz9sRC; Wed, 12 Jun 2024 17:25:23 +0000 (UTC) Received: from lazy.lzy (localhost [127.0.0.1]) by lazy.lzy (8.18.1/8.14.5) with ESMTPS id 45CHPMIr005360 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Wed, 12 Jun 2024 19:25:23 +0200 Received: (from red@localhost) by lazy.lzy (8.18.1/8.17.2/Submit) id 45CHPMYx005359; Wed, 12 Jun 2024 19:25:22 +0200 Date: Wed, 12 Jun 2024 19:25:22 +0200 From: Piergiorgio Sartor To: Paul E Luse Cc: Reindl Harald , Piergiorgio Sartor , linux-raid@vger.kernel.org Subject: Re: RAID-10 near vs. RAID-1 Message-ID: References: <20240611171433.375d6e25@peluse-desk5> Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240611171433.375d6e25@peluse-desk5> X-purgate-type: clean X-purgate: clean X-purgate-size: 1759 X-purgate-ID: 155817::1718213136-027FAA47-B159E847/0/0 On Tue, Jun 11, 2024 at 05:14:33PM -0700, Paul E Luse wrote: > On Wed, 12 Jun 2024 01:04:18 +0200 > Reindl Harald wrote: > > > > > > > Am 11.06.24 um 20:31 schrieb Piergiorgio Sartor: > > > I'm setting up a system with 2 SSD M.2 (NVME). > > > > > > I was wondering if would it be better, performace > > > wise, to have a RAID-10 near layout or a RAID-1. > > > > > > Looking around I found only one benchmark: > > > > > > https://strugglers.net/~andy/blog/2019/06/02/exploring-different-linux-raid-10-layouts-with-unbalanced-devices/ > > > > > > Which uses mixed SSD, NVME and SATA. > > > > > > Does anybody have any suggestions, links, or > > > ideas on the topic? > > > > > > BTW, practically speaking, what's the difference, > > > between the two RAIDs? > > > > i wouldn't even consider a RAID10 with two disks, especially with SSD > > and practically you end with a unsupported RAID1 because there are no > > stripes with 2 disks > > > > > I don't disagree but I would recommend you try each variation and > measure the performance for yourself. It's a great learning experience > if you haven't done it before and there's nothing like trusting your > own data over on your own system/config something that someone else has > done when there are so many factors that can affect performance. > > -Paul > Hi, thanks to you as well. About benchmarking, you're absolutely right, I did in the past for other RAIDs (-5, -6 and -10). I was just hoping to skip it, this time... :-) I do not have really a performance problem to solve. I'm just curious, given that the two RAIDs seem identical, if someone already tested the two. Thanks, bye, -- piergiorgio