公开(公告)号：US09355035B2

公开(公告)日：2016-05-31

申请号：US14082199

申请日：2013-11-18

Applicant: GLOBALFOUNDRIES Inc.

Inventor： Benjiman L. Goodman ,  Jody B. Joyner ,  Stephen J. Powell ,  William J. Starke ,  Jeffrey A. Stuecheli

IPC: G06F12/00 ,  G06F12/08

CPC classification number: G06F12/0828 ,  G06F12/0864 ,  G06F2212/621 ,  Y02D10/13

Abstract: A set associative cache is managed by a memory controller which places writeback instructions for modified (dirty) cache lines into a virtual write queue, determines when the number of the sets containing a modified cache line is greater than a high water mark, and elevates a priority of the writeback instructions over read operations. The controller can return the priority to normal when the number of modified sets is less than a low water mark. In an embodiment wherein the system memory device includes rank groups, the congruence classes can be mapped based on the rank groups. The number of writes pending in a rank group exceeding a different threshold can additionally be a requirement to trigger elevation of writeback priority. A dirty vector can be used to provide an indication that corresponding sets contain a modified cache line, particularly in least-recently used segments of the corresponding sets.

Abstract translation: 集合关联缓存由存储器控制器管理，存储器控制器将修改（脏）高速缓存行的回写指令放入虚拟写入队列中，确定包含修改的高速缓存行的集合的数量何时大于高水位标记，并且升高一个 回读指令优先于读取操作。 当修改集合的数量小于低水位时，控制器可以将优先级恢复为正常。 在其中系统存储器件包括等级组的实施例中，可以基于等级组映射一致等级。 超过不同阈值的等级组中挂起的写入次数还可以是触发提高回写优先级的要求。 可以使用脏向量来提供对应集合包含修改的高速缓存行的指示，特别是相应集合的最近最少使用的段。