Hi,

I currently have storage pools for block and file, ill just focus on the block side for now.

In my Block Pool I have NLSAS, 10KRPM, and fast cache is enabled. 

I have several LUNS that are basically at 100% Utilization.  I know utilization needs to be looked at with care because it doesn't mean we are at capacity.  Well all of the 10KRPM drives are at 35% utilization but 120 IOPS which is what I thought was the max for those drives. The response time and queue length maximums are also quite high. 

The fast Cache was put in recently but I don't really notice any difference when I compare the LUN utilization before and after Fast Cache was enabled on the Storage Pool.