Use the following formula to calculate the value of the MaximumSGList:
MaximumSGList = (BlockSize/4096) + 1
The procedure depends on the host bust adapter type: SCSI, Fibre Channel, or iSCSI. Before changing the block size for a particular host bus adapter card, see the vendor documentation or contact the vendor support.
As an example - Refer to following adaptec article for more details -