SCHEDULING STORAGE ACCESSES FOR RATE-GUARANTEED AND NON-RATE-GUARANTEED REQUESTS

摘要

A system for managing storage accesses for rate-guaranteed continuous multimedia data streams and non-rate-guaranteed storage requests may include a plurality of rate-guaranteed requestors for multimedia streams and one or more non-rate-guaranteed requestors. A disk scheduler may also be included. The disk scheduler may have a guaranteed rate queue for queueing storage requests from the rate-guaranteed requestors and a non-rate-guaranteed queue for queueing requests from the non-rate-guaranteed requestors. The disk scheduler may also include a bandwidth allocator coupled to the guaranteed rate queue and the non-rate-guaranteed queue and further coupled to a storage system. The bandwidth allocator may be configured to allocate bandwidth of the storage system between the guaranteed rate queue and the non-rate-guaranteed queue according to a predetermined ratio. The rate-guaranteed requestors may be limited so that an aggregate of maximum stream rates guaranteed for each rate-guaranteed requestor does not exceed the portion of the bandwidth allocated to the guaranteed rate queue. Requests may be ordered in the guaranteed rate queue according to a deadline. Requests may be ordered in the non-rate-guaranteed queue according to a priority. The system may also include a buffer ring for each multimedia data stream from one of the rate-guaranteed requestors.