From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Setting disk parameters in a VM Date: Sun, 15 Mar 2009 12:40:44 +0200 Message-ID: <49BCDB2C.60407@redhat.com> References: <49BA90B2.80804@tmr.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: KVM list To: Bill Davidsen Return-path: Received: from mx2.redhat.com ([66.187.237.31]:43983 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754426AbZCOKks (ORCPT ); Sun, 15 Mar 2009 06:40:48 -0400 In-Reply-To: <49BA90B2.80804@tmr.com> Sender: kvm-owner@vger.kernel.org List-ID: Bill Davidsen wrote: > Based on a discussion in another list on ioschedulers, I added a few > lines to my rc.local to set the scheduler to "noop" for disks with > model QEMU*, to the scheduling in the VM will not be computing with > the scheduling in the host. > > I wonder if the same thinking applies to the "rotational" feature > added to /sys/block in 2.6.29, intended for SSD but probably > appropriate for virtual and nbd devices as well. A virtual disk backed by a rotational physical disk probably should be marked rotational, at least with cache=off. -- error compiling committee.c: too many arguments to function