Netapp, Inc.

Sudheer Kumar Vavilapalli

Stephen Wu

Parag Sarfare

Asif Imtiyaz Pathan

Nikhil Mattankot

Amit Borase

Techniques are provided for implementing a persistent key-value store for caching client data, journaling, and/or crash recovery. The persistent key-value store may be hosted as a primary cache that provides read and write access to key-value record pairs stored within the persistent key-value store. The key-value record pairs are stored within multiple chains in the persistent key-value store. Journaling is provided for the persistent key-value store such that incoming key-value record pairs are stored within active chains, and data within frozen chains is written in a distributed manner across distributed storage of a distributed cluster of nodes. If there is a failure within the distributed cluster of nodes, then the persistent key-value store may be reconstructed and used for crash recovery.

Persistent key-value store and journaling system

Techniques are provided for a recovery process with selective ordering and concurrent operations in order to recover from a failure. Representations of active log structures are rebuilt within memory according to ordering values assigned to I/O operations logged within the active log structures. Representation of certain active log structures may be concurrently rebuilt based upon the active log structures comprising I/O operations that are non-overlapping within a distributed file system, have no dependencies, relate to different services, and/or target independent files. Representation of stale log structures are concurrently rebuilt within memory. While rebuilding the log structures and executing the I/O operations, a key value map is concurrently rebuilt within the memory for locating data of the I/O operations. Concurrent operations during the recovery process reduces the time to complete the recovery process, and thus reduces client downtime during the recovery process.

Growing community of inventors

Sunnyvale, CA, United States of America

Sudheer Kumar Vavilapalli