| 摘要 |
<p>In an audio/video server (100) blocks of data are read from a storage medium (110) by a reader (180) and supplied to users in the form of data streams. The storage medium (110) comprises a plurality of record-carrier based storage units (102, 104, 106, 108). A reader (180) reads a batch of data units from a storage unit in a single relative movement of a reading head of the storage unit with respect to the record-carrier of the storage unit. A scheduler (170) controls reading of blocks from the storage medium (110) by determining from which storage unit(s) data unit(s) need to be read for the block and placing a corresponding carrier access request in a read queue. The scheduler (170) extracts for each of the storage units a batch of carrier access requests from the queue and issues the batch to the reader (180) in an asynchronous manner, in response to the reader (180) having substantially completed reading data units for a previous batch for the storage unit.</p> |
