Atomic cache transactions in a distributed storage system

Abstract

An atomic write data structure is provided comprising a stripe buffer list descriptor defining state information of a stripe buffer list entry associating a virtual stripe of data storage space with cache data. An associated method is provided comprising constructing metadata associating a virtual stripe of data storage space with cache data; modifying the metadata to reflect state changes related to a pending data transaction between the data storage space and the cache; writing the modified metadata to an atomic write descriptor; and recalling the atomic write descriptor for transacting a selected atomic block size in an event of an interruption while executing the data transaction.

Description

FIELD OF THE INVENTION [0001] The claimed invention relates generally to the field of data storage and more particularly, but not by way of limitation, to an apparatus and method for atomic data transactions with a nonvolatile cache memory. BACKGROUND [0002] Computer networking began proliferating when the data transfer rates of industry standard architectures could not keep pace with the data access rate of the 80386 processor made by Intel Corporation. Local area networks (LANs) evolved to storage area networks (SANs) by consolidating the data storage capacity in the network. Users have realized significant benefits by the consolidation of equipment and the associated data handled by the equipment in SANs, such as the capability of handling an order of magnitude more storage than would otherwise be possible with direct attached storage, and doing so at manageable costs. [0003] More recently the movement has been toward a network-centric approach to controlling the data storage sub...

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