Metadata management for a transactional storage system

摘要

A method for managing metadata for a transactional storage system include receiving a query request at a snapshot timestamp. The query request requests return of at least one data block from a plurality of data blocks. Each data block includes a corresponding write epoch timestamp and a corresponding conversion indicator indicating whether the data block is active or has been converted at a respective conversion timestamp. The method also includes setting a read epoch timestamp equal to the earliest one of the write epoch and determining whether any of the respective conversion timestamps occurring at or before the snapshot timestamp occur after the read epoch timestamp. The method also includes determining the at least one data block requested by the query request by scanning each of the data blocks including corresponding write epoch timestamps occurring at or after the read epoch timestamp.