| 摘要 |
<p>In a data storage hierarchy a data-storage buffer (15) transfers data signals with other units (10, 14) in relatively large blocks of data (21). Such large blocks storable in large address spaces are not always filled with meaningful data. To more efficiently use the data-storage space in the data-storage buffer, the allocatable unit or segment (28) of the data buffer is made smaller than the data capacity of the large block. Each time a large block of data (21) is to be written into the data buffer, a sufficient number of the segments (23, 25, 27) for storing data of one large block is allocated for receiving the data. After the data of the one block is written into the data buffer, the allocated segments are examined: all of the allocated segments not storing data (25, 27) from the one large block are deallocated. The invention is particularly useful for data buffers acting as cached data storage for large-capacity direct-access storage devices (DASD) (14) and are coupled to host processors (10) programmed to operate with such DASD. The procedure is followed for data written into the caching data storage whether supplied by DASD or the host processors.</p> |
