VMware vSphere

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  • 1.  How to monitor frequency of physical cpu cores?

    Posted Nov 28, 2014 08:44 AM

    Hello,

    vSphere 5.5 U2

    How can i monitor frequency of physical cpu cores in realtime?



  • 2.  RE: How to monitor frequency of physical cpu cores?

    Posted Dec 11, 2014 11:32 PM

    Hi vm7user

    The closest you will probably get is esxtop

    Running this will show you the % usage per core.  So if you have a 2Ghz CPU and esxtop is showing 50% utilisation of both cores, both are running at 1Ghz.

    So you'll have to do some quick mental maths.

    The following is taken from Simon Greaves ESXTOP Guide http://www.simongreaves.co.uk/esxtop-guide/

    ===============


    Commands
    -S– Snapshot mode, prompts for the delay between updates, in seconds.
    -R– Path to the vm-support collected snapshot’s directory.

    CPU
    CPU load average of 1.00 means full utilisation of all CPU’s. A load of 2.00 means the host is using twice as many physical CPU’s as are currently available, likewise 0.50 means half are being utilised.

    CPU Screen
    PCPU USED(%)
    – Physical hardware execution context. Can be a physical CPU core if hyperthreading is unavilable or disabled or a logical CPU (LCPU) or SMT thread if hyperthreading is enabled. This displays PCPU percentage of CPU usage when averaged over all PCPUs.
    PCPU UTIL(%) – Physical CPU utilised. (real time) Indicates how much time the PCPU was busy, in an unhalted state, in the last snapshot duration. Might differ from PCPU USED(%) due to power management technologies or hyperthreading.

    If hyper threading is enabled these figures can be different, likewise if the frequency of the PCPU is changed due to power management these figures can also be adjusted.

    As an example if PCPU USED(%) is 100 and PCPU UTIL(%) is 50 this is because hyper threading is splitting the load across the two PCPUs. If you then look in the vSphere client you may notice that CPU usage is 100%. This is because the vSphere client will double the statistics if hyperthreading is enabled.
    In a dual core system, each PCPU is charged by the CPU scheduler half of the elapsed time when both PCPUs are busy.