Does disk reconstruction lead to performance impact?
Applies to
- ONTAP 9.x
 - Data ONTAP 8.x
 - Data ONTAP 7-Mode
 
Answer
- Data ONTAP completes reconstructs/rebuilds in the least impactful way by design, but still requires some system resources
 - For systems close to a resource bottleneck either at CPU or the disk layer, this can lead to an increase in overall latency
 - Potential mitigation options:
    
- Reduce the overall workload on the node if possible
 - Add disks which will spread workload across more spindles to increase the I/O bandwidth.
 - Move to SSDs which have more I/O bandwidth with decreased I/O latency.
 
 
Note: The process of rebuilding the data from parity from a failed drive is more impactful than performing a sick disk copy
