Performance Reporting

Not too long ago, I wrote a script for Script-O-Mania, the idea of the script was to gather CPU Ready times from VMs across one or more ESX hosts and display their values on a nice graph. I felt like this would be a useful tool because the only way to see the CPU Ready Time information in vCenter is on a VM by VM basis, there is no way to select a single host and see the CPU Ready Time for several VMs on a single graph. Since that particular counter can be useful in identifying sluggish VMs, I felt like it would be really useful to be able to see several VMs together as well as to compare VMs on one ESX host to another. The original script can be found on the Script-O-Mania contest page.

After writing that script, I thought it could be even more useful if it could be used for other performance counters besides just CPU Ready and also if instead of grouping the VMs just by the ESX host, if I could group them by any object that is visible in vCenter such as a cluster, folder, resource pool etc. In vCenter the graphs you see for these objects contain specific counters pertinent to those objects, the performance tab does not allow you to graph VMs that contained in the specified group object.

I used PrimalForms 2009 to make it more user friendly with a GUI front end. To use this little app, please make sure you have the following prerequisites installed.

Prerequisites:
- Powershell 2.0
- PowerCli
- Microsoft Excel 2007
- The underlying Powershell script is not signed, so set your Powershell settings accordingly

Feel free to leave your comments and suggestions.

Download here

Quick Hit - New vSphere 4 Storage Features

Paravirtualized iSCSI

What: This is a driver for high performance storage adapters

Benefits: It offers greater throughput and lower CPU utilization

When to use it: For very I/O intensive applications

VMDirect I/O for Storage

What: Enables VMs to directly access the underlying hardware

Benefits: Enhances CPU efficiency in applications with constant and frequent I/O

Drawbacks:
     1) VMotion is not available
     2) HBA is not shareable by other VMs

Virtual Disk Thin Provisioning

What: Space is allocated on an as-needed basis in 1 MB chunks

Benefits:
     1) Improves storage efficiency
     2) Increases utilization rates
     3) Reduces storage costs

Drawbacks: You could over provision the disks and run out of space, so monitoring of resources is essential.

How to Enable Hot Add CPU and Memory in vSphere

In vSphere, there is a new feature, hot add memory and CPU. This is very cool as downtime can be avoided which is, at least in my company, very helpful during daily operations. This feature is not enabled by default. To enable these features, do the following:

1. Make sure the virtual machine hardware is upgraded to version 7, if it is not, then right click the VM and choose 'Upgrade Virtual hardware'. You can find the hardware version by clicking on the 'Summary' tab.



2. Go to edit settings for the VM, then the options tab, under 'Advanced', select 'Memory/CPU hotplug' and in the pane to the right, enable the memory hot add and CPU hot plug features. This change must be made when the VM is powered down. If the VM is running, the options will be greyed out as in the image below.



Hot add memory and CPU is not supported by all OS's, Windows 2008 Enterprise 64 bit edition is one of the suppoted OS's, for a complete list, take a look at the Guest OS Guide.