Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am tricked with the results seen from the Memory performance report in VM Guest Server (Windows 2008 R2); taken with the Perfmon Counters are no way related with the performance reports I got from vCenter Server. I am trying to compare both in guest Perfmon reports to vCenter reporting VM Performance report. Can anybody please help me understand the differences and the factors causing it.


share|improve this question

My guess is that vCenter reports memory consumption of the whole guest machine (including the overhead needed for running it). So perf. monitor on the guest reports performance "from the inside" and vCenter reports performance "from the outside" of VM.

Could you give more info about the "are no way related with the performance reports"?

share|improve this answer
Hi, In guest Windows is reporting VM memory usage as 50% when taken counters from Perfmon and from Task manager and Resource MOnitor. However looking at the vCenter Server windows Performance reports for VM; that's when i go to performance tab of particular VM, it showing about 20% usage of Memory only. – chaladi Apr 22 '13 at 15:33
It could be that guest os (Win) reports the virtual memory and vCenter reports actually used memory. I recollect there is some kind of issue with virtual memory on Win7 so it could happen on W08R2 ( ). Do your guest and hypervisor report the same amount of memory? – Fiisch Apr 22 '13 at 16:18

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.