Write-back cache protection
AssigneeEMC Corporation
InventorKenneth P. Der
Life of this patent
Estimating the term…
Abstract
A technique protects host data. The technique involves receiving, at a local computerized node, a block of data from a host computer, the block of data including data sub-blocks. The technique further involves storing the block of data, as a dirty cache block, in a local cache of the local computerized node. The technique further involves performing a set of external caching operations to cache a set of sub-blocks in a set of external computerized nodes in communication with the local computerized node. Each external caching operation caches a respective sub-block of the set of sub-blocks in a cache of a respective external computerized node. The set of sub-blocks includes (i) the data sub-blocks of the block of data from the host and (ii) a set of checksums derived from the data sub-blocks of the block of data from the host.
Claims20
A local computerized node, comprising:
- a communications interface to connect to a host computer and a set of external computerized nodes;
- a local cache;
- and
- a controller coupled to the communications interface and the local cache, the controller being constructed and arranged to:
- receive, through the communications interface, a block of data from the host computer, the block of data including data sub-blocks,
- store the block of data, as a dirty cache block, in the local cache, and
- perform, through the communications interface, a set of external caching operations to cache a set of sub-blocks in the set of external computerized nodes, each external caching operation caching a respective sub-block of the set of sub-blocks in a cache of a respective external computerized node, the set of sub-blocks including (i) the data sub-blocks of the block of data from the host computer and (ii) a set of checksums derived from the data sub-blocks of the block of data from the host computer.
A computer program product including a non-transitory computer readable storage medium which stores a set of instructions to protect host data, the set of instructions, when run on a processor of a local computerized node, causing the local computerized node to:
- receive, at the local computerized node, a block of data from a host computer, the block of data including data sub-blocks;
- store the block of data, as a dirty cache block, in a local cache of the local computerized node;
- and
- perform a set of external caching operations to cache a set of sub-blocks in a set of external computerized nodes in communication with the local computerized node, each external caching operation caching a respective sub-block of the set of sub-blocks in a cache of a respective external computerized node, the set of sub-blocks including (i) the data sub-blocks of the block of data from the host computer and (ii) a set of checksums computed from the data sub-blocks of the block of data from the host computer.
A method of protecting host data, the method comprising:
- receiving, at a local computerized node, a block of data from a host computer, the block of data including data sub-blocks;
- storing the block of data, as a dirty cache block, in a local cache of the local computerized node;
- and
- performing a set of external caching operations to cache a set of sub-blocks in a set of external computerized nodes in communication with the local computerized node, each external caching operation caching a respective sub-block of the set of sub-blocks in a cache of a respective external computerized node, the set of sub-blocks including (i) the data sub-blocks of the block of data from the host computer and (ii) a set of checksums generated from the data sub-blocks of the block of data from the host computer.
Dependencies are inferred from the claim text.