VCP-VMC 2024 Question 173
Single answerA company is experiencing degraded performance in their VMware Cloud environment. The environment is built on VMware vSphere and includes several virtual machines running critical workloads. Upon investigation, you notice high CPU Ready times on multiple virtual machines. What is the most effective way to reduce CPU Ready times and improve performance?
- A
Increase the number of vCPUs allocated to the affected virtual machines.
- B
Reduce the number of vCPUs allocated to the affected virtual machines.
- C
Migrate the affected virtual machines to hosts with lower CPU utilization.
- D
Enable CPU affinity to bind each virtual machine to specific physical CPU cores.
Show answer and explanation
Correct answer: C
Explanation
CPU Ready time occurs when a virtual machine is waiting for physical CPU resources to become available. High CPU Ready times typically indicate contention for CPU resources on the host. Migrating virtual machines to less-utilized hosts redistributes the load and reduces contention, which is the most effective solution to this issue. Other options either do not address the root cause (contention) or introduce additional complexities.
- A. Incorrect.
Increasing the number of vCPUs can worsen CPU Ready times as it increases contention for physical CPU resources, especially if there is already resource contention on the host.
- B. Incorrect.
Reducing the number of vCPUs may help marginally, but it is not the most effective solution if high CPU utilization and contention are the primary causes of the issue.
- C. Correct.
Migrating the affected virtual machines to hosts with lower CPU utilization reduces contention for CPU resources, effectively lowering CPU Ready times and improving performance.
- D. Incorrect.
While enabling CPU affinity can provide dedicated CPU resources, it is generally not recommended as it reduces flexibility in resource scheduling and might lead to underutilization of physical CPUs.