Skip to main content
NetApp Knowledgebase

How to collect WAFLTOP output from cli

Applies to

  • Data ONTAP 8 7-Mode 
  • Clustered DATA ONTAP 8.3 
  • ONTAP 9.0 and later

Description

  • 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
    • CPU
    • Disk I/O
    • Memory
    • 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
Terminology:
  • 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.
Use Cases:
  • 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.

 

 

 

 

CUSTOMER EXCLUSIVE CONTENT

Registered NetApp customers get unlimited access to our dynamic Knowledge Base.

New authoritative content is published and updated each day by our team of experts.

Current Customer or Partner?

Sign In for unlimited access

New to NetApp?

Learn more about our award-winning Support

 

 

 

  • Was this article helpful?