We have been watching CPU and memory resources on a VM by using the built in Windows Resource Monitor as well as the vCetner Performance tab and the data doesn't seem to be consistent. For example this morning Resource Monitor showed a 30 second spike in CPU to 100% but if I do a CPU view of that time period in the vCenter Performance area for CPU it doesn't show up there. Is one more accuarate than the other?
The performance charts in vCenter vary in the collection periods and rollups. I think they breakdown as follows:
Real time = every 20 seconds
Daily = every 5 minutes
Weekly = every 30 minutes
Monthly = every 120 minutes
Yearly = every 24 hours
It sounds like you might be getting caught up in between rollups. It's best if you take look at the performance troubleshooting guide and see if that helps you out. It's a great doc and covers esxtop as well.
I ran a utility on a VM that maxes out the processor. Windows Performance Monitor and Resource Monitor showed the processor at 100%. The real time view in vCenter showed it at 100% as well but when I do a custom time frame view then it doesn’t show the spike on the chart for some reason.
Which Perfmon counters are you using and is VMware tools installed and up to date.
I was using the VM memory and VM processor counters but noticed something while playing around.
Its seems as though when you do a set time period for a chart in vCenter that it may take an average because I ran a tool that maxes out the CPU and it showed up in real time mode but not in a custom time period mode when I ran it for a minute. But when I ran it for 5 minutes or so it would then show up in the custom time frame chart as if it had 100% CPU usage long enough to show up on the chart.
The performance charts in vCenter vary in the collection periods and rollups. I think they breakdown as follows:
Real time = every 20 seconds
Daily = every 5 minutes
Weekly = every 30 minutes
Monthly = every 120 minutes
Yearly = every 24 hours
It sounds like you might be getting caught up in between rollups. It's best if you take look at the performance troubleshooting guide and see if that helps you out. It's a great doc and covers esxtop as well.
If thats the case for the collection intervals that that would totally explain it. Thanks for the info!