Take the following items into consideration when enabling CPU power saving with Dynamic Carbon Reduction:
- The status of CPU power saving is NON_POWER_SAVING by default.
- You cannot specify the following two settings at the same time: enabling the CPU power saving mode and setting the load monitoring period.
- Because the CPU frequency is decreased while CPU power saving is in POWER_SAVING status, the I/O response performance is degraded. Do not enable the CPU power saving mode if you require quick response, even when the load is low on the storage system.
- After detecting an increased load on the storage system, this function takes about 2 to 3 seconds until switching the status of CPU power saving from POWER_SAVING to NON_POWER_SAVING. While the status is being switched, the storage system performs the same as in POWER_SAVING status, even in a high load environment.
- When capacity saving is enabled, garbage collection and post processes run regularly, so the devices less frequently become idle. In such circumstances, this function might not provide sufficient power saving effect.
- While an MP is blocked or a maintenance that requires recovery operations (such as, firmware replacement, controller maintenance, or planned stoppage or startup) is performed, the status of CPU power saving does not change to POWER_SAVING regardless of the actual CPU load. Also, when a failure (such as, MP blockade, controller blockade, or FAN failure) occurs, the status of CPU power saving does not change to POWER_SAVING regardless of the actual CPU load.