Transaction VL10A performance issues

Hi,

How can VL10A pefromance be improved?

VL10A takes about 1 hour to process 500 sales orders to subsequent deliveries. Time consuming query is AUSP which uses N02 index(Include LCLSCF2B) and FM RV_DELIVERY_CREATE consumes more time. User role set for 1. 'VL10BATCH' can't be used because of schedueling.

Thanks