CentOS - Jul 2007 - xen network io load

Hello

I have Xen related issues. I try to describe it as best as I can. 
While transmitting large amounts of data from domU the IO load
increases greatly, thus making the domU unusable. The load is
significant even on dom0. The performance of cpus and hard drives is
not an issue. We have this problem on all servers with diferent hw
configurations. Please do you know the reason of this behaviour, do you
have any experience whith such problems?


-- 
S pozdravem 

Tadeas Mengler
Senior Linux System Administrator

tadeas.mengler at miton.cz
483 367 866, 608 264 866
  
MITON CZ, s.r.o. | miton.cz
Jiraskova 9, 466 01  Jablonec nad Nisou
Tel.: 483 367 800, fax: 483 710 884
   
stahuj.cz | stable.cz | otoman.cz | vareni.cz

On Mon, Jul 16, 2007 at 09:55:15AM +0200, Tadeas Mengler
wrote:
> Hello
> 
> I have Xen related issues. I try to describe it as best as I can. 
> While transmitting large amounts of data from domU the IO load
> increases greatly, thus making the domU unusable. The load is
> significant even on dom0. The performance of cpus and hard drives is
> not an issue. We have this problem on all servers with diferent hw
> configurations. Please do you know the reason of this behaviour, do you
> have any experience whith such problems?
> 
Nope, no such experience with many xen hosts. 

How do you measure this "IO load" ? What effects does it have? 

What kind of hardware do you have (cpu/mem/nic/disk or raid controller/disks)? 

Are you running centos5? latest updates installed? 

-- Pasi