A.Enable Storage IO Control.
B.Configure Storage DRS.
C.Enable the Dynamic Queue Depth Throttling option.
D.Configure the Disk.SchedNumReqOutstanding parameter.
SIOC is extremely powerful, it canincrease your consolidation ratios on the storage side, allowing
more VM’s per datastore. Which leads to lower storage costs and less administrative overhead.
So how does it work? At a basic level SIOC is monitoring the end to end latency of a
datastore.When there is congestion (the latency is higher than the configured value) SIOC
reduces the latency by throttling back VM’s who are using excessive I/O. Now you might say, I
need that VM to have all of those I/O’s, which in many cases is true, you simply need to give the
VMDK(s) of that VM a higher share value. SIOC will use the share values assigned to the VM’s
VMDK’s to prioritize access to the datastore.
Just simply turning SIOC on will guarantee each VMDK has equal access to the datastore, shares
finetune that giving you the ability to give VMDK’s more or less priority during times of contention.