System for supplying data steams

A system for retrieving blocks of data from a storage medium and supplying the data to users in the form of a plurality of at maximum nmax data streams;

• wherein each data stream is in one of a plurality of states including at least a new and an active state, where a data stream upon creation is in the new state in which no sufficient data is present for consumption by a user and where for an active data stream a user may consume data;
• said system comprising:
• for each data stream an associated buffer for storing data;
• and
• a reader for reading in one sweep from the storage medium for each data stream of a selected group of data streams a predetermined size data block and for storing the read data blocks in the buffers associated with the data streams;
• a scheduler for repeatedly selecting the group of data streams for which a data block of a predetermined size needs to be read during a next sweeping operation of the reader;
• the group comprising active data streams whose associated buffers have room for storing the data block;
• and causing the reader to read data for the selected group;
• characterised in that:
• the scheduler is operative to minimize access time by variably determining the size of the data block for each next sweeping operation through an expression that, with respect to a number of data streams, is substantially based on an actual number nact of active data streams.