From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Garman Subject: Re: Array Power Management Date: Thu, 10 Sep 2009 11:51:56 -0500 Message-ID: <20090910165156.GA30820@sewage> References: <292245.77763.qm@web55804.mail.re3.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <292245.77763.qm@web55804.mail.re3.yahoo.com> Sender: linux-raid-owner@vger.kernel.org To: linux-raid List-Id: linux-raid.ids On Sun, Sep 06, 2009 at 08:48:03PM -0700, jahammonds prost wrote: > I can do this on single drives using hdparm -S to set the spindown > timeout, and the disks will spin up on activity as needed. Is > there something similar I can do with an md array? I can see > there's a /sys/block/md0/power/wakeup file, but I can't seem to > find any documentation on it. I have thought about doing an hdparm > -S on the array disks, but I suspect that would be A Bad Thing > (tm). On the same note, does anyone have any thoughts on the wear-and-tear caused by frequent spinup/spindown cycles? My fileserver has the Western Digital RE2 "enterprise" grade drives. I remember reading (years ago) that, in general, "enterprise" grade drives were designed to be always running (think 24/7 server), and rarely spun down. As such, they did not tolerate a "consumer desktop" usage pattern very well, and trying to save power in this way would actually cause them to fail prematurely. Is/was such a thing true? Is it worth worrying about? Thanks, Matt