Method for reducing buffer capacity in a pipeline processor

A method to reduce buffer capacity in a processor includes giving the data packets admittance to the processor through at least one interface, storing the data packets in at least one input buffer, and using a packet rate shaper outside of a processing pipeline to control flow of the data packets to the pipeline before the data packets enter the pipeline. First and second data packets are given admittance to the pipeline in dependence on cost information per packet that is dependent upon an expected time period of residence of the first data packet in the pipeline. Cost information dependent upon an expected time period of residence of the second data packet in the pipeline differs from said cost information dependent upon the expected time period of residence of the first data packet in the pipeline.