You are right. Switching to a mirror RAID configuration would definitely ease off the load of parity calculations from the Service Processors.  Having said that can you please enlighten us about the SP configuration or CX4 model? How are you determining that the parity calculations are causing heavy load on SPs. Also, CX4 doesnt seem to be an underpowered system, so parity calculations should not be a problem. Can you also provide some information about you IO workload? (Total IOPS, Read to write ratio, etc.)
I have a CX4 with service processors that are too overloaded. I'm wondering if RAID5 parity calculations are done here. I have a fair amount of available disk but not enough horse power in the SP's to service them. I'm wondering if going to a RAID1 or RAID10 for our write intensive apps might lessen the load on the SP's. It would certainly lessen the backend IOPS. All thoughts greatly appreciated.
Where does the parity calculation happen. At the SPs?