BENTONVILLE, Ark. — Walmart is getting tougher on its vendors, with plans to announce even stricter penalties for incomplete fill rates than in the past. The company will expect large suppliers to deliver full orders within one or two days 85% of the time. Failure to meet the requirement will result in a fine of 3% of the cost of delayed goods. Previously, suppliers had a 75% threshold before incurring fines. Smaller vendors will fare a little better. They will have to meet the on-time requirement 50% of the time, up from 33%. The change will take effect in April. Increased inventory management is one way Walmart and others are trying to compete online more effectively against Amazon.