Netapp, Inc.

Network Appliance, Inc.

Bruce Leverett

Michael Kazar

Peter Frank Corbett

Alan Stuart Driscoll

Devang Kundanlal Shah

Srishylam Simharajan

Toby Smith

Narayana R Tummala

Richard Parvin Jernigan, Iv

Jason S Bertschi

Vasilis J Apostolides

Mandayam C Srivas

A method and apparatus for replicating a data container of a source storage server at the logical level in an unordered stream of individual data units are described. In certain embodiments, the replication operations can be performed without regard to the differences in geometry of physical persistent storage of the source and destination storage servers and without regard to the differences in data container format of the source and destination storage servers. An initial replication operation of the source data container is performed by transferring the data objects within the source data container to a replica data container in the destination storage server as an unordered stream of individual data units while preserving data object identifiers of the source data objects. Afterwards, incremental replication operations can be performed to capture modifications to the source data container over time after the initial replication operation.

Unordered idempotent logical replication operations

A technique for permitting multiple virtual file system having the same VFS identifier to be served by a single storage system. A data frame descriptor data structure is modified to include a storage pool index value that indexes into a storage pool array to identify a storage pool descriptor. The storage pool (SP) descriptor includes a SP ID, which is used in conjunction with a VFS ID to uniquely identify the VFS to which dirtied data is to be written.

Technique for permitting multiple virtual file systems having the same identifier to be served by a single storage system

At least certain embodiments disclose a method and apparatus for replicating a file system at the logical block level in an unordered stream of individual data units. In at least certain embodiments, the replication operations include creating a snapshot of a file system of a source storage system, identifying changes in the file system since a previous replication operation by comparing the snapshot with a previous snapshot created during the earlier replication operation, and asynchronously transferring the identified changes to a destination storage system in an unordered stream of individual data units.

Unordered idempotent replication operations

A technique for accelerating the creation of a hyperclone of a virtual file system. Specifically, each data block and indirect block directly referenced by a base inode are only copied. The hyperclone may then reference the original data blocks and original indirect blocks. Further, an indication may be provided for at least one of the copied data blocks and indirect blocks that indicates that the at least one of the copied data blocks and indirect blocks is in use.

Technique for accelerating the creation of a point in time representation of a virtual file system

A system and method for replaying a log file without performing a total cache flush. The log replay is performed in three phases, a pre-processing phase that determines which portions of the log file are to be replayed, a redo phase where certain transactions are redone and an undo phase where certain transactions are rolled back. After performing the log replay only the data dirtied during the undo phase is flushed from the cache, thereby decreasing the amount of time required for the log replay operation.

Technique for accelerating log replay with partial cache flush

A system and method for accelerating file deletion by preloading indirect blocks. When processing level 1 (L1) indirect blocks, the file server issues a read request for the next N indirect blocks to be loaded into a buffer cache. The file server processes the indirect blocks from the buffer cache without requiring multiple single block disk accesses. Once the N indirect blocks have been processed, a read request for the next N L1 indirect blocks is then sent. The technique permits parallel processing by loading indirect blocks to be processed while previously cached indirect blocks are being processed.

Technique for accelerating file deletion by preloading indirect blocks

A technique for accelerating the creation of a hyperclone of a virtual file system. A hyperclone inode is copied from the base inode. Each indirect and direct block referenced by the base inode is also copied and the block pointers within the base inode are set to reference the copied direct data blocks. A CTW bit is set within each copied block that alerts the file system that the reference indirect or direct block is not to be deallocated.

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Pittsburgh, PA, United States of America

Bruce Leverett