From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bill Davidsen Subject: Disk characteristics for virtual machines Date: Fri, 13 Mar 2009 12:51:58 -0400 Message-ID: <49BA8F2E.9030704@tmr.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: Linux RAID List-Id: linux-raid.ids Justin (jpiszcz@lucidpixels.com) was discussing the ioscheduler for SSD, and I was thinking about that in terms of virtual machines, since I run a lot of small servers using KVM. So I added a short script to my rc.local, to use the "noop" scheduler for any drive with model QEMU* so that the underlying host scheduling can work without anything competing. I was wondering if that should also apply to the "rotational" feature added in 2.6.29, since these "devices" are backed by files. Ref: -- Bill Davidsen "Woe unto the statesman who makes war without a reason that will still be valid when the war is over..." Otto von Bismark