From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carlos Mennens Subject: Re: RAID1 On 3 Drives Date: Mon, 15 Mar 2010 09:47:25 -0500 Message-ID: References: <4B9C11FB.7040604@gmx.net> <4B9C24B6.7040507@tmr.com> <70ed7c3e1003150548v65dce098ud62ddfbcc0747d49@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <70ed7c3e1003150548v65dce098ud62ddfbcc0747d49@mail.gmail.com> Sender: linux-raid-owner@vger.kernel.org To: Mdadm List-Id: linux-raid.ids On Mon, Mar 15, 2010 at 7:48 AM, Majed B. wrote: > Carlos, > > Choosing your RAID setup depends on the purpose of your machine. Is it > a web server, file server, archive, mail, video storage, ...etc. Basically this is my everyday workstation that I keep everything on. It's not hosting Apache or MySQL or anything like that. Just my everyday workstation. > /boot is only used during boot up. Having a spare on stand by or not > does not affect performance, except in the case a disk dies; in that > case, the hot spare is engaged and becomes an active disk at which the > array starts to resync the data to this new disk. During resyncing, > performance will be degraded. Oh, I was wondering why Bill noted previously that a spare would hurt performance but based on your info above, this is only if a drive fails and then the spare starts to synchronize. I hope that is what Bill meant. > As for your RAID5 question: I think if your usage of the server is > write-mostly, you may find it to have better performance with 3 disks > rather 4. If it's read-mostly, then 4 disks should perform better. > > If you have physical access to the machine, try both cases. Setting > them up won't take more than 5-10 minutes. Benchmarking wouldn't take > more than 15 minutes in each setup. > > Remember, there are parameters to fine-tune: NCQ, read-ahead, noatime, > nodiratime, chunksize, ...etc. I do have access to the machine as it's my new Desktop PC I am building today at some point. I just wanted to get some expert advise on how I should proceed. For now I am going to use all 4 disks with no spares. I just don't know enough about fine tuning and how it could benefit or hinder disk performance for my setup so I guess I will omit them until I can understand what to use for what function. If you guys have any suggestions for what parameters to use for /boot, /, or swap...please feel free to chime in. Thanks all!