Xen 
 
Home About Xen.org Xen Xen Summit Wiki Mailing List Bug Tracker Xen Downloads
 
   
 

xen-users

Re: [Xen-users] TAP:AIO much slower then file: ?!

To: MS <ms@xxxxxxxxxx>
Subject: Re: [Xen-users] TAP:AIO much slower then file: ?!
From: "Javier Guerra" <javier@xxxxxxxxxxx>
Date: Thu, 31 Jul 2008 09:04:18 -0500
Cc: xen-users@xxxxxxxxxxxxxxxxxxx
Delivery-date: Thu, 31 Jul 2008 07:05:56 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4891BB6F.6010709@xxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <4891BB6F.6010709@xxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
On Thu, Jul 31, 2008 at 8:17 AM, MS <ms@xxxxxxxxxx> wrote:
> Hi!
>
> i checked the io performance with bonnie++ on an domU.
> With "file:" i get a goot result (nearly the dom0 results):

that "440M" is the test size? if so, it sounds too small.  it should
at least be twice (5-10x is better) the size of cache available.
remember, "file:" devices might be cached by the Dom0, "tap:" won't.
with small files it's common to see this pattern on most tests, but
won't benefit most real world uses.


-- 
Javier

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users

<Prev in Thread] Current Thread [Next in Thread>