8 By using operating system performance monitors, such as the Microsoft Performance Monitor utility for Windows operating systems or the iostat command for Linux operating systems. Collect data for a minimum of one day. Collecting this information impacts on performance and therefore the collection period should be long enough to gather a true representation of usage but not too long. The first procedure described below, to collect data characteristics for the VMs via the vSphere Client console performance statistics, uses
a timeframe of one day and the second procedure, to collect data characteristics for the VMs by running a scri pt to collect the data characteristics uses a timeframe of seven days.
Note: When running vCenter Server versions before version 5.x, if any of the virtual machines use NFS storage, metrics for the
NFS storage are not generated by the vCenter Server. To collect data characteristics for the VMs via the vSphere Client console performance statistics:
1. In the vSphere Client console select the VM and open the Performance tab.
2. Click Advanced
3 . Click the Charts Options link. The Customize Performance Chart dialog is displayed.
4. In Chart Options , drill-down in Disk and select Past day
5. In Counters , click None to clear all the selections and then select Disk Write Rate or Write Rate
6. Click OK