Data streaming system utilizing an asynchronous technique for retrieving data from a stream server

A system for retrieving blocks of data, such as audio and/or video data, from a storage medium and supplying the blocks in the form of a plurality of data streams to users;

• the storage medium including a plurality of record-carrier based storage units;
• the block including at least one data unit, where a data unit is stored on one of the storage units;
• the system comprising:
• reader means, for each of the storage units, for servicing a batch of carrier access requests by reading a corresponding batch of data units in a single relative movement of a reading head of the storage unit with respect to the record-carrier of the storage unit;
• each unit of the batch of data units being associated with one of the carrier access requests of the batch of carrier access requests;
• and
• scheduler means for controlling reading of data blocks for the data streams from the storage units by:
• determining for at least one data unit of each block in which storage unit the data unit is stored and placing a carrier access request in a read queue;
• the carrier access request being associated with the data unit and the determined storage unit;
• and
• cyclically extracting for each of the plurality of storage units a batch of carrier access requests associated with the storage unit from the read queue in an asynchronous manner, by for each individual storage unit, issuing a batch of carrier access requests for the storage unit to the reader in response to the reader having substantially completed reading data units for a previous batch of carrier access requests for the storage unit;
• and
• issuing the batches to the reader.