| 摘要 |
<p>Cache memory lines are dynamically paged out to underlying storage in accordance with their current levels of activity and are clustered for paging purposes on the same basis. Activity measures are assigned to each line when it is paged into cache; these measures are updated whenever a cached line is re-accessed. When space is needed in the cache for new lines, the activity measures are sorted based on their relative activity levels and those lines that are least active are grouped onto pages and paged out together. In this manner, the currently most active lines are retained in the cache; and lines having the same temporal characteristics and access frequencies are grouped together on the same page, thereby increasing the likelihood that when a new line is brought into the cache, the other lines that are on the same page, and hence that are brought into cache along with requested line, will themselves soon again become active.</p> |
