WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-users

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

To: Javier Guerra <javier@xxxxxxxxxxx>, xen-users@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-users] TAP:AIO much slower then file: ?!
From: MS <ms@xxxxxxxxxx>
Date: Thu, 31 Jul 2008 16:49:52 +0200
Cc:
Delivery-date: Thu, 31 Jul 2008 07:50:34 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <90eb1dc70807310704n71cc1f79n7f3fb567b6abb511@xxxxxxxxxxxxxx>
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> <90eb1dc70807310704n71cc1f79n7f3fb567b6abb511@xxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Thunderbird 2.0.0.16 (Windows/20080708)
Tastsite 440M needs over a hour with tap:aio:
If i use some more i have to wait .... to christmas :)
With file: the 440M need less then 3 minutes.

I know, 440M is not a good value, but it never can be less then 1% of the performance before changeing.

Javier Guerra schrieb:
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.




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

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