SYSTEMS AND METHODS FOR PERSISTENT CACHE LOGGING

摘要

A cache log module stores an ordered log of cache storage operations sequentially within the physical address space of a non-volatile storage device. The log may be divided into segments, each comprising a set of log entries. Data admitted into the cache may be associated with respective log segments. Cache data may be associated with the log segment that corresponds to the cache storage operation in which the cache data was written into the cache. The backing store of the data may be synchronized to a particular log segment by identifying the cache data pertaining to the segment (using the associations), and writing the identified data to the backing store. Data lost from the cache may be recovered from the log by, inter alia, committing entries in the log after the last synchronization time of the backing store.

主权项

1. A method comprising:
storing data directed to a backing store in a cache; recording an ordered sequence of log entries on a persistent storage medium, wherein each log entry corresponds to a set of one or more storage operations; and maintaining associations between data stored in the cache and the log entries at least until the data stored in the cache is stored on the backing store.