Method, system and program products for managing changed data of castout classes
    14.
    发明授权
    Method, system and program products for managing changed data of castout classes 失效
    用于管理变更数据的方法,系统和程序产品

    公开(公告)号:US06230243B1

    公开(公告)日:2001-05-08

    申请号:US09251888

    申请日:1999-02-19

    IPC分类号: G06F1200

    摘要: Changed data of castout classes of a coupling facility cache are managed in order to be able to efficiently determine the age of the oldest changed data in the cache. A directory entry representing a changed datum is placed in a data structure corresponding to the castout class of the changed datum. The data structure includes an order queue ordered by timestamps and a process queue, having an ordered portion and an unordered portion. When the directory entry is to be added to the data structure, an attempt is first made to place the entry on the order queue. If the entry is not placed on the order queue within a predefined amount of time, then the entry is placed on the process queue, the order of which is maintained by background tasks. In order to return the oldest entry of the data structure, the smallest entry of the process queue is determined and that entry is then compared to the smallest entry of the order queue. The smaller of those two entries corresponds to the oldest entry for the castout class.

    摘要翻译: 管理耦合设施高速缓存的丢弃类的更改数据,以便能够有效地确定高速缓存中最早更改的数据的年龄。 表示更改的数据的目录条目被放置在与改变的基准的castout类相对应的数据结构中。 数据结构包括由时间戳排序的订单队列和具有有序部分和无序部分的处理队列。 当目录条目要添加到数据结构中时,首先尝试将条目放在订单队列上。 如果条目未在预定义的时间内放置在订单队列上,则该条目将被放置在进程队列中,其顺序由后台任务维护。 为了返回数据结构的最旧条目,确定进程队列的最小条目,然后将该条目与订单队列的最小条目进行比较。 这两个条目中较小的条目对应于castout类的最旧条目。