From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Buehler <aspam@cox.net>
Subject: Re: probable vm exit latency issue?
Date: Fri, 15 Dec 2017 15:24:37 -0500
Message-ID: <5A342F85.9070406@cox.net>
References: <5A342458.9010403@cox.net> <mL8E1w02Z1iuWrx01L8FMi>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: kvm@vger.kernel.org
To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Return-path: <kvm-owner@vger.kernel.org>
Received: from eastrmfepo201.cox.net ([68.230.241.216]:38639 "EHLO
        eastrmfepo201.cox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1755530AbdLOUYk (ORCPT <rfc822;kvm@vger.kernel.org>);
        Fri, 15 Dec 2017 15:24:40 -0500
Received: from eastrmimpo109.cox.net ([68.230.241.222])
          by eastrmfepo201.cox.net
          (InterMail vM.8.01.05.28 201-2260-151-171-20160122) with ESMTP
          id <20171215202439.HAZN4103.eastrmfepo201.cox.net@eastrmimpo109.cox.net>
          for <kvm@vger.kernel.org>; Fri, 15 Dec 2017 15:24:39 -0500
In-Reply-To: <mL8E1w02Z1iuWrx01L8FMi>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

Konrad Rzeszutek Wilk wrote:

> Um. Don't use IDE? Use VirtIO.

I will revert to virtio.  It was virtio originally, I changed it to ide since that is what is used on the box the works.

Perhaps the difference between boxes is not the driver but the fact that the working box has an SSD disk and the new box has rotating disks.

To eliminate disk I/O entirely I am trying Ubuntu's "overlayroot".  However, I am still getting enormous latency from ata_bmdma_start calls, just nowhere near as often.

Joe Buehler