- Data ONTAP 8 7-Mode
- Clustered DATA ONTAP 8.3
- ONTAP 9.0 and later
- Traditional tools like sysstat have provided CPU and I/O utilization information on a system-wide basis.
- No way to be able to map resource utilization information to volume or application workloads.
- The 'wafltop' command allows visibility of top consumers of system resources
- Disk I/O
- NVLOG utilization
- This allows for correlation of controller resource utilization to volume/application workloads.
- The 'wafltop' command will provide information about the topmost consumers of the CPU, I/O memory or NVlog resources:
- WAFL volumes
- Client file system protocols like NFS, FCP, CIFS, ISCSI and others which call into WAFL
- Protocols like RSM, SPINNP
- Consistency point / Write allocation processes
- WAFL messages
- CPU Utilization - Collected for kahuna, wafl_exempt, xcleaner domains. CPU utilization refers to the percentage of CPU cycles used.
- Latency histograms - System (internal) and client latency.
- Disk I/O operations - Reads and writes from disk in MB and in terms of RAID messages.
- NVLog utilization - NVLog utilization for normal CPs and b2b CPs. NVlog utilization is shown in terms of average percentage of the log used per CP.
- Memory utilization(Debug only) - shows buffer cache and inode cache usage. Memory utilization is in terms of MB used.
- I/O Utilization- I/O utilization refers to the amount of data read or written in MB/s.
- Customer sees some degradation in performance, say in terms of throughput or response time, on some/all of the nodes in a cluster.
- Customer wishes to determine if there is a volume or a particular application or client protocol which is consuming resources in a way that leads to the degradation.
- Customer can look at the output of cluster 'wafltop' to determine the topmost consumers of various system resources in a cluster. Based on this information, the customer may be able to narrow down to the cause of the degradation.