From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brad Campbell Subject: Re: Home desktop/server RAID upgrade Date: Wed, 04 Jun 2014 20:29:16 +0800 Message-ID: <538F111C.9070206@fnarfbargle.com> References: <20140530212907.0b00e8a3@netstation> <5389B463.5020100@hesbynett.no> <8mtskybo2j1i4l2bqu51l7ll.1401554092920@email.android.com> <538B4173.3030202@hesbynett.no> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Mark Knecht , David Brown Cc: Craig Curtin , "L.M.J" , Linux-RAID List-Id: linux-raid.ids On 01/06/14 23:59, Mark Knecht wrote: > > These VMs are the area where my current RAID6 (5 drive, 16k chunk > size) seems to have been a bad decision. The machine is powered off > every night. Loading these VMs takes at least 10-15 minutes each > morning where I see disk activity lights just grinding away the whole > time. If I had a single _performance_ goal in upgrading the disks it > would be to improve this significantly. Craig's SSD RAID1 suggestion > would certainly help here but at 240GB there wouldn't be a lot of room > left. That may be OK though. > Just a data point. I run between 4 & 10 VM's here 24/7 (always 4, sometimes 10). I started them out on a 3 drive RAID-5 on 7200RPM disks, then migrated them across to a RAID-10 of 15k SAS drives, and from there to a 6x240GB RAID-10 of SSD's. I would _never_ go back to rotating media now. Some of my batch tasks in a Windows 7 VM took up to an hour on the disks. I'm down to 20-30 minutes max now. Granted my workload is pretty atypical. Much less power, less noise and less heat. Lots to love. 240GB drives are a bit of a price sweet spot, and still were when I bought these 6 over a year ago. I just went with 3 from Intel and 3 from Samsung just to spread the risk a little bit. 3 are on the MB AHCI controller and 3 on an LSI SAS. Regards, Brad -- Dolphins are so intelligent that within a few weeks they can train Americans to stand at the edge of the pool and throw them fish.