How is CPU Contention (%) calculated

Products

• VMware Aria Suite

Issue/Introduction

You need clarity on how the CPU Contention metric is identified and analyzed in VMware Aria Operations.

Environment

VMware Aria Operations 8.x

Resolution

1. Navigate to a VM page in Aria Operations
2. Click the Metrics tab
3. Expand Metrics > CPU and hover the cursor over the CPU Contention (%) metric
   
   

   Percentage of time VM is not getting the CPU time. Value is the sum of CPU overlap, ready, co-stop and other wait

When using the default 5-minute collection cycle, Aria Operations collects the 15 latest 20 second metric points from vCenter to identify the number of ms that the VM CPU was in one of the 4 constituent states (overlap, ready, co-stop and other wait) then divides by the 300,000 ms in the 5-minute period and multiplies by 100 to get a percentage.

Additional Information

For a detailed discussion of VM CPU Contention, review the free eBook vSphere Metrics: Deep dive into VMware vCenter and ESXi performance and capacity counters authored by Iwan Rahabok

VCF Operations Transformation, 4th Edition