[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Regarding TX/RX rings


  • To: James Harper <james.harper@xxxxxxxxxxxxxxxx>
  • From: Mahendra Kutare <mahendra.kutare@xxxxxxxxx>
  • Date: Sat, 23 Oct 2010 09:05:57 -0400
  • Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
  • Delivery-date: Sat, 23 Oct 2010 06:07:18 -0700
  • Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; b=IIbqnx4uH9oKBmeolcV+s+3nTSNb+v82RqPDl2j4SkiNLAJD/lQRkqTpYpj5xMAx3G DajUEUKbp6s9ArKSuxKNuzXuUVo0JDyzko2O8RkfiJ5VkqBSqaZwHzplHvWKx1JmxYO2 B6FLNtH2Oa31atuv9u0q0vsQ1LaEZS+LeNJnI=
  • List-id: Xen developer discussion <xen-devel.lists.xensource.com>

Can you point me to the code files which would be good starting point for the monitoring mentioned below ?

Regards
Mahendra

On Sat, Oct 23, 2010 at 8:35 AM, James Harper <james.harper@xxxxxxxxxxxxxxxx> wrote:
>
> The reason I am looking to monitor these rings is to find the variability of
> the data transfer through the TX/RX rings i.e. inbound/outbound network
> traffic. I am doing variability analysis for various combination of VMs
> running in Xen. I am looking at both CPU and Network level metrics. The goal
> is to infer characteristics looking at these lower level metrics about the VMs
> running.
>
> On my current installation of Xen 3.4.3 with 2.6.18.8 kernel , Âthe data
> mentioned in /sys/devices/vbd- or /sys/devices/vif is not available. I need to
> upgrade my kernel.
>
> I have seen that if I monitor the network traffic input and output throughput
> data (through say xentop running application - RUBiS) it does not really vary
> a lot. So I want to monitor the lower levels to see if there exists
> variability that eventually evens out.
>

Monitoring just the rings will not tell you about tx-full or rx-starvation conditions. You would also need to measure when DomU wants to transmit a packet but there is no space left on the tx ring, or when Dom0 has a packet for DomU but Dom0 has used all of the rx buffers given by DomU. I would find those measurements useful.

James

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

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.