Had to leave the Maintaining High NAS Performance Levels: Celerra Performance Analysis and Troubleshooting session early which was a little disappointing because I was enjoying it.
Once again posting this quickly so please excuse any spelling and grammar errors. Also if you find any information that is incorrect please comment.
Notes from the session:
Start performance troubleshooting by characterizing the workload (Note: this is performance troubleshooting 101 regardless of platform)
- Rate (IOPs)
- Size (Transfer Size / KB)
- Direction (Read/Write)
Key Celerra commands for looking at performance data:
Protocol stats summary for CIFS and NFS:
server_stats server_x -summary nfs,cifs -interval=10 =count=6
- Determine Protocol type and R/W ratio
Protocol stats summary for NFS only:
server_stats server_x -summary cifs -i 10 =c 6
Investigate response times:
server_stats server_x -table nfs -i 10 -c 6
Where is the I/O destined for (which file system):
server_stats server+x -table fsvol -i 10 -c 6
- Look for a I/O balance across available resources
Where is the I/O destined for (basic volumes):
server_stats server+x -table dvol -i 10 -c 6
- Again look for a I/O balance across available resources
A high level of activity on root_ldisk is usually indicative of a high number of ufslog messages
server_log server_x | tail –f
Hoping some of my peers took some notes after I departed the session and hopefully I can post them later today.