LSI Assigned Three Patents

Snapshot metadata management in storage system

LSI Corp., Milpitas, CA, has been assigned a patent (8,356,148) developed by five co-inventors for a "snapshot metadata management in a storage system."

The co-inventors are Vladimir Popovski, Irvine, CA, Nelson Nahum, Tustin, CA, Alexander Lyakas, Haifa, Israel, Ishai Nadler, Kfar Saba, Israel, and Moshe Melnikov, Israel.

The abstract of the patent published by the U.S. Patent and Trademark Office states: "Methods and systems for improving performance in a storage system utilizing snapshots are disclosed by using metadata management of snapshot data. Specifically, various metadata structures associated with snapshots are utilized to reduce the number of IO operations required to locate data within any specific snapshot. The number of IO operations are reduced by allowing the various metadata structures associated with the temporally current snapshot to locate data directly within any temporally earlier snapshot or on the original root volume."

The patent application was filed on Sept. 22, 2009 (12/564,291).

Coupling sub-LUN load measuring metadata size
to storage tier utilization in dynamic storage tiering

LSI Corp., Milpitas, CA, has been assigned a patent (8,386,708) developed by Martin Jess, Erie, CO, for a "method for coupling sub-LUN load measuring metadata size to storage tier utilization in dynamic storage tiering."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A method for metadata management in a storage system configured for supporting sub-LUN tiering. The method may comprise providing a metadata queue of a specific size; determining whether the metadata for a particular sub-LUN is cached in the metadata queue; updating the metadata for the particular sub-LUN when the metadata for the particular sub-LUN is cached in the metadata queue; inserting the metadata for the particular sub-LUN to the metadata queue when the metadata queue is not full and the metadata is not cached; replacing an entry in the metadata queue with the metadata for the particular sub-LUN when the metadata queue is full and the metadata is not cached; and identifying at least one frequently accessed sub-LUN for moving to a higher performing tier in the storage system, the at least one frequently accessed sub-LUN being identified based on the metadata cached in the metadata queue."

The patent application was filed on Sept. 21, 2010 (12/887,190).

Cache synchronization for SSDs

LSI Corp., Milpitas, CA, has been assigned a patent (8,352,690) developed by four co-inventors for a "cache synchronization for SSDs."

The co-inventors are Carl Forhan, Rochester, MN, Timothy Swatosh, Rochester, MN, Pamela Hempstead, Oronoco, MN, Timothy Lund, and Michael Hicken, Rochester, MN

The abstract of the patent published by the U.S. Patent and Trademark Office states: "Described embodiments provide a media controller that synchronizes data cached in a buffer and corresponding data stored in one or more sectors of a storage device. A buffer layer module of the media controller caches data transferred between the buffer and the storage device. One or more contiguous sectors are associated with one or more chunks. The buffer layer module updates a status corresponding to each chunk of the cached data and scans the status corresponding to a first chunk of cached data. If, based on the status, the first chunk of cached data is more recent than the corresponding data stored on the storage device, a media layer module synchronizes the data on the storage device with the cached data. The status corresponding to the group of one or more sectors is updated. The media layer module scans a next chunk of cached data, if present."

The patent application was filed on March 24, 2010 (12/730,627).