there is a SLES12SP2 on a HyperV and this host has a RAW-SAN connection.

But even if there is heavy load at the SAN-Store the waitstaits
increasing to much. (Sometimes they reach 80!)

At the old system (SLES11) at a phys. host but with the same SAN we have
never such high waitstaits.

What should be the next steps to increase the perfomance?