= CPU utilization in ONTAP is not a linear measure of the system load, nor can it be used alone as a

measure of the overall system utilization. ONTAP uses a Coarse Symmetric Multiprocessing (CSMP)

design which partitions system functions into logical processing domains, each with its own

scheduling rules and resource availability. Therefore, a high CPU utilization does not necessarily

indicate a performance problem, unless it is accompanied by other contributing factors such as high

latency, low throughput, or high queue depth. ONTAP has several mechanisms to optimize CPU

usage and balance the workload across the cores, such as WAFL parallelization, exempt processing,

and CPU pinning. The CPU utilization reported by the sysstat command is an average across all cores

and domains, and does not reflect the actual CPU activity or availability for each domain. Therefore,

the CPU is not a first-order monitoring metric for ONTAP, and other metrics such as latency,

throughput, and queue depth should be considered first. Reference = What is CPU utilization in Data

ONTAP: Scheduling and Monitoring?, How to measure CPU utilization, What are CPU as a compute

resource and the CPU domains in ONTAP 9?, Monitoring CPU utilization before ONTAP upgrade