Analysis of retrieval of multimedia data stored on magnetic tape

This paper discusses scheduling of random I/O requests for multimedia data stored on magnetic tape using serpentine data layout. Results from simulations and real experiments show that substantial improvements of retrieval performance can be achieved by proper I/O scheduling. A new algorithm, Multi-Pass Scan Star (MPScan*), is presented and shown to give better results than any other known algorithm. The level of quality of service that can be reached by use of MPScan* is discussed in the context of retrieval of image and short video segment data.