From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: poor I/O performance on domU Date: Mon, 17 Jan 2005 10:00:10 -0600 Message-ID: <1105977610.29654.3.camel@localhost> References: <41E69C98.7090804@fzu.cz> <1105635651.25281.2.camel@localhost> <41E6AB02.6020801@fzu.cz> <1105637082.25283.12.camel@localhost> <41E92A7D.9070405@fzu.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <41E92A7D.9070405@fzu.cz> Sender: xen-devel-admin@lists.sourceforge.net Errors-To: xen-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Jan =?ISO-8859-1?Q?Kundr=E1t?= Cc: xen-devel List-Id: xen-devel@lists.xenproject.org On Sat, 2005-01-15 at 08:36, Jan Kundr=E1t wrote: > Anthony Liguori wrote: > yes, dom0 filesystems are on partitions located on hda. My theory is that since hda is a single disk if you've got dom0 reading and writing to it and another partition reading and writing to the same disk at the same time both are going to be slower than if you were just writing to hda on dom0. That's why I suggest trying it with a neutral device. > I've tried exporting /dev/hda7 (not used neither mounted from dom0) as=20 > sdb7 and I can get about 12.3 MB/s. From dom0 I get about 14.8 MB/s. That seems pretty reasonable. Doesn't seem like there's a problem.=20 Sharing partitions between dom0 and domU seems like a bad idea. Look through the threads in the list about filesystem corruption. > Tested by `time dd if=3D/dev/{s|h}hda7 of=3D/dev/null bs=3D1M`, about 4= .5GB of=20 > data. >=20 > -jkt --=20 Anthony Liguori Linux Technology Center (LTC) - IBM Austin E-mail: aliguori@us.ibm.com Phone: (512) 838-1208 ------------------------------------------------------- The SF.Net email is sponsored by: Beat the post-holiday blues Get a FREE limited edition SourceForge.net t-shirt from ThinkGeek. It's fun and FREE -- well, almost....http://www.thinkgeek.com/sfshirt