Which action should be taken?

Users are complaining that a Windows application server virtual machine configured with 1GB RAM is not performing satisfactorily. The virtual machine is in a fully automated DRS cluster. An administrator opens the Performance tab for the guest virtual machine and adds the counters for Memory Ballooned and Memory Swapped in MB. The performance chart displays a value of 0 for Memory Ballooned and 240 for Memory Swapped.

Which action should be taken?

A.
Install VMware Tools into the virtual machine.

B.
Adjust Mem.CtlMaxPercent to read 75.

C.
Migrate the virtual machine to another host.

D.
Add memory to the virtual machine.

5 Comments on “Which action should be taken?

  1. dimaped says:

    Correct answer is C. Swapped memory at the host level means Memory contention at the host level rather that at the guest level.

    1. Jon says:

      It’s in a fully automated DRS cluster though. If it just needed to be moved over to a different hosts, DRS would take care of that. The host is definitely in memory contention though, and the fact that DRS isn’t moving the VM off would indicate that other hosts in the cluster are similarly constrained.

      VMtools would install the balloon driver into the guest. Instead of the host swapping out part of the guest memory, it would allow the ballon driver to do it’s job and let the guest OS choose the least important pages in memory to swap out, therefore freeing up memory for the host while allowing important pages necessary for performance to stay in memory.

  2. Mohsin Alvi says:

    Balloon Driver help Host to get memory from the VM so that memory can be used by other VMs. But in question, Balloon Driver would not help VM mean installing VMtools will not do nothing
    ESXi host swap out the VM when it is in memory contention (swapping is one of the ESXi memory management technique that it use when no option left) so i think best answer is Migrate the VM to another Host
    But Host is the part of DRS that is fully automatic that making this question confuse (why VM not migrate to another Host in Cluster ?)

    the Answer can be the due to some constraints on VM level like CPU Affinity rules etc…

  3. Josti says:

    First I thought D.

    There is just 1 GB configured, so migrating isnt going to give it more memory, besides its configured for DRS so it would have done that itself.

    I thought the fact that it is swapping means that it has not enough memory available?
    But then I rememberd that the VM first tries to Baloon and then tries compression and then uses Swapping. The fact that it is swapping and not doing any balooning, means its not working and thus the driver needs to be installed.


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