You have a customer who is concerned with high CPU and disk utilization on their SnapMirror destination system. They are worried about high CPU and…

SnapMirror is a data replication technology that allows efficient and flexible data protection and

disaster recovery for NetApp ONTAP storage systems1

SnapMirror transfers data between source and destination volumes using a network

connection. SnapMirror can use storage efficiency features such as compression and deduplication to

reduce the amount of data transferred and stored1

SnapMirror transfers are scheduled and controlled by policies that define the frequency, retention,

and priority of the transfers. SnapMirror policies can also specify the network bandwidth limit for the

transfers2

SnapMirror transfers are considered background tasks that run in the absence of user

workload. SnapMirror transfers can consume CPU and disk resources on both source and destination

systems, depending on the amount and type of data being replicated3

SnapMirror transfers can throttle up or down depending on the availability of system resources and

network bandwidth. SnapMirror transfers will throttle up when there is no user workload, and

throttle down when there is user workload. This is to ensure that SnapMirror transfers do not impact

the performance of user operations3

Therefore, if a customer is concerned with high CPU and disk utilization on their SnapMirror

destination system, the best answer is to explain that background tasks such as SnapMirror throttle

up in the absence of user workload. This is normal and expected behavior, and it does not indicate a

problem with the system3

Reference:

1: ONTAP 9 Data Protection - SnapMirror - The Open Group 2: ONTAP 9 Data Protection - SnapMirror

Policies - The Open Group 3: SnapMirror storage efficiency configurations and behavior - Resolution

Guide - NetApp Knowledge Base