I/O Storage controller cache system with prefetch determined by
requested record's position within data block
    1.
    发明授权
    I/O Storage controller cache system with prefetch determined by requested record's position within data block 失效
    具有预取的I / O存储控制器缓存系统由所请求的记录在数据块内的位置确定

    公开(公告)号:US4490782A

    公开(公告)日:1984-12-25

    申请号:US270951

    申请日:1981-06-05

    摘要: In a data processing system of the type wherein a host processor transfers data to or from a plurality of attachment devices, a cache memory is provided for storing blocks of data which are most likely to be needed by the host processor in the near future. The host processor can then merely retrieve the necessary information from the cache memory without the necessity of accessing the attachment devices. When transferring data to cache from an attachment disk, additional unrequested information can be transferred at the same time if it is likely that this additional data will soon be requested. Further, a directory table is maintained wherein all data in cache is listed at a "home" position and, if more than one block of data in cache have the same home position, a conflict chain is set-up so that checking the contents of the cache can be done simply and quickly.

    摘要翻译: 在其中主机处理器向多个附接装置传送数据或从多个附件装置传送数据的数据处理系统中,提供高速缓冲存储器用于存储在不久的将来最可能由主机处理器需要的数据块。 然后,主机处理器可以仅从高速缓存存储器中检索必要的信息,而无需访问附件设备。 从附件磁盘传输数据到缓存时,如果很可能要求这个附加数据可能会同时传输附加的未请求的信息。 此外,保持目录表,其中高速缓存中的所有数据都列在“本地”位置,并且如果高速缓存中的多于一个数据块具有相同的原始位置,则建立冲突链,以便检查 缓存可以简单而快速地完成。

    Automatic adjustment of the quantity of prefetch data in a disk cache
operation
    2.
    发明授权
    Automatic adjustment of the quantity of prefetch data in a disk cache operation 失效
    在磁盘缓存操作中自动调整预取数据量

    公开(公告)号:US4489378A

    公开(公告)日:1984-12-18

    申请号:US270750

    申请日:1981-06-05

    摘要: When transferring data to a cache memory from an attachment data storage device, additional unrequested information can be transferred at the same time if it is likely that this additional data will soon be requested. The average quantity of data transferred to the cache memory in each operation can be automatically and continually varied in order to maximize the performance advantage provided by the cache memory. When a record of data is requested by the host processor, data is transferred to the cache memory from an attachment data storage device in increments of fixed-length data blocks each containing a sequence of data records, with the number of transferred blocks being determined by the position of a requested data record in its respective data block, and the average number of blocks transferred in any one operation being varied by adjusting threshold position values at which second or third data blocks are transferred.

    摘要翻译: 当从附件数据存储设备传送数据到高速缓冲存储器时,如果很可能要求这个附加数据,则可以同时传送额外的未请求的信息。 在每个操作中传输到高速缓冲存储器的数据的平均数量可以被自动地和连续地变化,以便最大化缓存存储器提供的性能优势。 当主处理器请求数据记录时,数据以固定长度的数据块的增量从附件数据存储设备传送到高速缓冲存储器,每个固定长度数据块包含一系列数据记录,传送块的数量由 通过调整传送第二或第三数据块的阈值位置值来改变在其各自的数据块中所请求的数据记录的位置以及在任何一个操作中传送的块的平均数量。