Picking screen get block when there are large number of records to process

Test Case:
1. Go to facility -> Picking (https://localhost:8443/facility/control/PicklistOptions?facilityId=WebStoreWarehouse)
2. Enter the number of order you want to group in 'Group first' text box. (Default value is 50 orders)
3. Click on Submit button.

Expected Result: On submitting, number of orders grouped should be equal to number of orders specified in the 'Group first' text box.

Manage Picklist screen get block when there are large number of records to process