- Would I expect this data to be consistent with the VNX arrays?
- VMAX and VNX arrays are like Orange vs Apple. Setting Round Robin IOPS to 1 on VNX is not the best practice. When I worked at EMC as a vSpecialist we recommended changing this setting to 50 or 100 depending on your workload. When I worked with a customer we tuned this setting on a mixed workload environment and 50 was the sweet spot.
2.Using this data, I'd only moidify this setting if I could demonstrate my storage traffic was predominantly sequential. What is the best way to determine the storage characteristics of my environment?
- I would not agree to this, you can benefit from this setting if your IOs are Random too. Imagine your DB is sending 500 Random IOs if your setting is default at 1000 you would only use one path. If the setting was 50 then requests would be divided in to 10 paths.
3. I suppose if I could identify enough predominantly sequential VMs to support a seperate sequential cluster that might make sense.
- Not necessarily refer to my answer in question 2 above. There are tools to identify your IO characteristics. A good start is ESXTOP or Remote ESXTOP. You can ask your EMC presales and partner presales to run an assessment on your VNX and VMware hosts. They can send you instructions to enable performance logging on VNX and enabling ESXTOP on VMware hosts. You will upload the logs and receive a very nice powerpoint presentation of your environment.