Understand CPU Overcommitment
CPU overcommitment lets you provision more virtual CPUs than the servers physically provide. It can improve utilization and revenue, but aggressive ratios create contention when workloads become busy together.
Calculate the ratio
Allocated vCPUs ÷ Available CPU threads
A server with 32 CPU threads hosting 48 vCPUs has an overcommitment ratio of 1.5:1.
When it works
Overcommitment works when workloads do not all require peak CPU at the same moment. Quiet workloads leave capacity that active workloads can use.
Know the risk
If too many workloads become busy together, the host may run out of CPU capacity. The result can be reduced performance, higher latency, and unhappy customers.
Recommended approach
Start close to 1:1, increase gradually, and monitor host utilization. A range around 1.25:1 to 1.5:1 can be a reasonable starting point, but the right value depends on workload behavior and CPU performance.