Frequency-based selective caching strategy in a continuous media server

We propose a frequency-based selective caching scheme where the buffer allocation unit varies with the access frequency of the requested object. With this scheme, buffer allocation works either at the distance level or object level. Once a request is admitted, it is sent to the disk(s) directly if the average arrival rate for the requested object does not exceed the marginal arrival rate. A distance between the requested stream and the preceding one accessing the same object is cached as a function of the length of the distance and the size of the buffer cache. An object is cached in its entirety, i.e., its caching mode can be changed into object mode if the average distance among the current streams for that object exceeds the average distance of the total number of current cached streams in the buffer cache. Our conclusion derived from the simulation is that our proposed caching scheme is more effective than other caching policies such as LRU and interval when it is applied to continuous media data