the system is a z9 BC with zVM 5.3 in Lpar 1 as the only running system on the machine. No second level just a normal VM/VSE system, not something special. My colleague has told me, he had such a behaviour at another site some time ago and it was a defect channel, where VM tried a permanent recovery. Maybe that one of the converter channels or an osa has a problem. We will try to configure one channel after the other offline and see what will happen.

kind regards
Franz Josef Pohlen



Kris Buelens schrieb:
My guess is that this VM system is second level (probably under LPAR, but a host VM would yield the same). The involuntary CPU waits imposed by the first level (LPAR or CP) is not known to IND LOAD, it is taken as busy. If the first level host decides your zVM gets e.g. 50% of the entire system, and this zVM want to use 50% or more: IND LOAD will display 100% busy as the zVM never places itself in voluntary wait. Logically your zVM system is indeed 100% busy (it cannot execute more instructions than it currently does); physically it gets 50%. And, if you sum up what is used in zVM, you will get at 50% indeed.

I don't know the HMC monitor enough to know if you can see logical and physical CPU busy for an LPAR.

When the entire system is not heavily loaded, and capping isn't turned on, then the difference between logical and physical CPU usage is small. Maybe this system got a bit more load making that the involuntary waits are no longer neglectable.

2008/11/24 [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> <[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>>

    There is no perfomance monitor. I had written a rexx procedure
    which issues an IND USER for each machine every minute and
    calculates from the difference to the value of the minute before
    the cpu consumption for this single machine. IBM in Germany (in
    Person Hans Joachim Ebert, meanwhile a retired VSE/CICS expert
    from IBM Munich) has compared the values from my procedure with a
    real monitor and it was nearly the same. The result of this
    procedure is that the added cpu consumption of the measured users
    is not more than 50%.

    The main purpose for this procedure was to get an estimate of the
    cpu usage if customers have no monitor. So unfortunately I cannot
    look into details.


    kind regards
    Franz Josef Pohlen



    Rich Smrcina schrieb:

        Do you have a performance monitor that can help you narrow
        down if a specific VSE machine is the culprit?

        [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> wrote:

            Hello listers,

            I have installed zVSE 4.1.1 und zVM 5.3 (Level 0703) at a
            customer where we replaced vm/vtam with an additional 4th
            zVSE machine with only vtam running for cross-domain
            between three zVSE4 systems. Before the change of the
            environment the customer was on zVSE 4.1.0. <http://4.1.0.>

            The added cpu consumption of the running guests is between
            40-50% but the IND LOAD and the activity on HMC shows
            permanently between 85 and 100% cpu usage. This creates of
            course massive performance problems.

            I have no clue what process(es) may create this additional
            load. We have restarted the zVM but it didn't help. If you
            put e. g. a batch job on the zVSE the cpu load of the zVSE
            rises as expected to 30-50% and the the vm load as
            indicated by IND LOAD is between 85 and 100%. Except of
            the production VSE the load of the other machines
            including VM tcpip, FTPSERVE and any others can be almost
            neglected (in sum below 10%).
            There are no error msgs from hardware which could explain
            such a behaviour.

            For documentation I have attached the user direct entries
            of the vse systems, the system config, the autolog profile
            and the cms profile of the VSE systems.

            Has anybody experienced such a behaviour of zVM and an
            idea where to look for the error. I know that the IND LOAD
            cpu value is rounded over a period of time, but I have
            never seen a difference greater than 5 - 10% to the added
            cpu% of the running systems.






--
Kris Buelens,
IBM Belgium, VM customer support

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