Patent ID: 7627724
Filing Date: 2009-12-01
Classification: G06F

Abstract:
1. In a computer system including a volatile memory and a persistent storage medium, a method for indicating the freshness of changeable data associated with a container, comprising: updating a fresh test table stored in the volatile memory of the computer system (“in-memory fresh test table”) with entries identifying each item of changeable data associated with a new container in the volatile memory (“in-memory container”) each time a new in-memory container is created; creating a new container stored in the persistent storage medium (“persistent container”) by merging all the in-memory containers associated with the at least one same item of changeable data; associating the new persistent container with a list identifying all items of changeable data associated with the new persistent container, wherein the list associated with the new persistent container further includes a Birthday value recorded in a header of a widset associated with the new persistent container; incrementing the Birthday value in the list associated with the new persistent container when the new persistent container appears in the list; and marking as invalid older versions of the items of changeable data in lists associated with older persistent containers, prior to marking as invalid older versions of the items of changeable data, in response to determining that the older persistent container does not contain the changeable data, determining whether there is another changeable data that has to be processed.