Every time I saw IOPS in Azure I always thought that what the heck is this. I understood the concept but never gave a hard look at it. The developer in me just glanced over it and just selected a VM size that felt good enough.
The issue becomes when you have to evaluate virtual machine size that is ideal for your workload so you don’t blow up your budget by selecting larger VMs or have performance issues with applications by selecting smaller VMs.
So one of the parameters you will have to consider is IOPS, i.e. I/O per sec for disk and network. While you can monitor for performance counters it is not the most intuitive way. Iometer is a free tool which you can use to measure these metrics and do some benchmarking. If you have existing VMs you can use this tool and figure out which VM size in Azure you might need.
In the below screen shot I am trying to measure performance of my regular drive.
And in the next test I am measure performance of my SSD drive. You can see the difference between two drives. SSDs are faster.
Please share you tips and tricks or article regarding measuring and benchmarking for IOPs performance.