Xen users - Mar 2007 - performance and resource monitoring and statistics

Hi,
    I am planning to monitor performance metrics of Dom0 and DomUs  (CPU
,Memory,Disk I/O ,Netowrk I/O) .....and define benmchmarks/thresholds to
allocate resources accoring to the performance metrics.I am using xm top and
Xenmon  to collect these metrics.

1)Any suggestions as to how i should go about defing these metrics.? The
metrics given out by  Xenmon   are a bit unclear.Could anyone give some link
which describes these parameters.

2)And are there performance thresholds defined for virtualized enviroment
like Xen.

Any updates on the follwoing post would be helpful.
Thanks..........


Henning Sprang wrote:
> Hi,
> Apart from normal service availability and quality monitoring and
> measuring of ressources on a system as it would be done for any normal
> machine, I think about additionally monitoring Xen-specific data and
> creating one/some Nagios plugins for this.
>
> So one idea is that I want to know when cpu, net and disk I/O on a Xen
> host are saturated, which could, depending on specific needs and
> SLA''s, make it necessary to add ressources to the host or migrate
VM''s
> to other hosts on which these ressources aren''t saturatd yet, or
> aother measures.
>
> While, as far as I understand it, CPU scheduling and traffic shaping
> are highly  useful to set rules to allocate a given share of the
> available ressources to specific vm''s, and set minimal and maximal
> amounts of these shares, in some cases it might be desirable to get
> more information, and be warned.
>
> As a result of this, I started to analyze (with a nagios plugin)
> different sources of xen runtime data, beginning with the output of
> xentop -b -i 2, and will mgo on to look deeper into libxenstats,
> XenMon and xenoprof(of which I am not yet sure if it''s good for
> analyzing production runtime data, or if it''s more the kind of
> profiling one does in non-production environments).
> Getting CPU share and seeing when the CPU is fully loaded is no great
> deal.
> Getting useful information of net and disk I/O saturation requires a
> lot of math and measuring (what''s the maximum possible net/disk
I/O on
> that machine, under the given configuration? ) -  they both are
> depending on overall hardware, cpu scheduling and a lot of other
> factors - I am really not sure if this is worth the trouble.
>
> I am at the same time working on implementations and looking at
> information and publications on that topic, like multiple papers on
> XenMon available, and so on.
>
> Did anybody else think about this, or anybody has comments if this is
> the right direction to think or better/concrete data to collect and
> look at?
>
> Henning
>