摘要 |
A data access control system for reading/writing data from/to an array of storage units, which is resilient to read/writing errors to avoid lost data, while meeting the realtime requirements. Consecutive data blocks are stored in a plurality of storage units in a distributed manner by using a striping technique. A time slot vacancy monitor checks the present activities of the storage units to find a vacant time slot during which no data read/write operations are scheduled. A data read/write controller finds a particular data block that is scheduled to be read out of/written the storage units just after the vacant time slot has expired. When such a data block is found, the data read/write controller prefetches that data block during the vacant time slot. If a read/write error is encountered during the prefetch of the data block, the data read/write controller attempts read/write retry operations in the remaining period of the vacant time slot until the scheduled data output time comes. This read/write retry operation will be repeated, if necessary, within the limited time period.
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