NetApp Assigned Four Patents

Transparently between nodes in clustered storage system
NetApp, Inc., Sunnyvale, CA, has been assigned a patent (8,751,533) developed by Poonam Dhavale, Susan M. Coatney, and Steven S. Watanabe, Sunnyvale, CA, for a “method and system for transparently between nodes in a clustered storage system.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A method and system are provided for transparently migrating a storage object (aggregate) between nodes by one of the nodes (source), automatically verifying another node (destination) is configured to service the aggregate, and changing ownership of the aggregate based on the verifying to enable servicing of the aggregate at the destination. A cluster manager receives an aggregate migration request and provides the request to the source owning the aggregate. The source verifies the destination is configured according to a predetermined configuration for servicing the aggregate. Based on the verifying, the source offlines the aggregate and updates ownership information of the aggregate, thereafter allowing the destination to online the aggregate. The cluster manager provides the updated ownership information to all nodes in the cluster, so an access request intended for the aggregate may be received by any node and forwarded to the destination using the updated ownership information.”

The patent application was filed on Nov. 25, 2009 (12/626,551).

Determining read-ahead length in storage system
NetApp, Sunnyvale, CA, has been assigned a patent (8,732,406) developed by Douglas Michael Pase, Raleigh, NC, Rickard Faith, Hillsborough, NC, and Matti Vanninen, Cary, NC, for a “mechanism for determining read-ahead length in a storage system.”

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A storage system tracks statistical behavior of client read requests directed to a storage device to form prediction about data that the client will require next. The storage system collects the size of read sequences for various streams into a data structure, which summarizes past behavior of read requests. This data structure reports the number of streams in each equivalence class of stream sizes that is tracked. The data structure is then used to determine expected size of a selected read stream. The data structure is also used to improve predictions about an expected size computed by a known technique.”

The patent application was filed on March 15, 2011 (13/048,486).

Reliability based data allocation and recovery in storage system
NetApp, Sunnyvale, CA, has been assigned a patent (8,732,518) developed by Mark W. Storer, Walnut Creek, CA, and Jiri Schindler, Jamaica Plain, MA, for a “reliability based data allocation and recovery in a storage system.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A storage system provides highly flexible data layouts that can be tailored based on reliability considerations. The system allocates reliability values to logical containers at an upper logical level of the system based, for example, on objectives established by reliability SLOs. Based on the reliability value, the system identifies a specific parity group from a lower physical storage level of the system for storing data corresponding to the logical container. After selecting a parity group, the system allocates the data to physical storage blocks within the parity group. In embodiments, the system attaches the reliability value information to the parity group and the physical storage units storing the data. In this manner, the underlying physical layer has a semantic understanding of reliability considerations related to the data stored at the logical level. Based on this semantic understanding, the system has the capability to prioritize data operations on the physical storage units according to the reliability values attached to the parity groups.”

The patent application was filed on April 13, 2011 (13/086,267).

Implementing unordered delivery of data between nodes in clustered storage system
NetApp, Sunnyvale, CA, has been assigned a patent (8,751,598) developed by Hari Shankar, Sunnyvale, CA, for a “method and system for implementing an unordered delivery of data between nodes in a clustered storage system.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “Described herein is a novel technique for implementing an unordered delivery (UOD) of write logs between nodes in a cluster to optimize processing resources during log mirroring operations. A mirroring entry may be generated for each write log in a local log cache constituting the write log and an order indicator for the write log. The order indicator may be, for instance, a storage location of the write log in the local log cache. The mirroring entry may then be forwarded across a network from the local node to the remote node, where the mirroring entry may be stored at a next available location of an interim cache at the remote node independent of the write log storage location in the local log cache.”

The patent application was filed on Nov. 3, 2010 (12/938,554).