Selective mirroring in caches for logical volumes

A method comprising:

• receiving an Input/Output (I/O) request from a host directed to a Logical Block Address (LBA) of a logical volume;
• consulting indexing information for a multi-device cache for the logical volume, in order to identify a cache line for storing data associated with the I/O request;
• storing the data at the cache line on a first device of the cache;
• mirroring the data to another device of the cache if the I/O request is a write request, wherein mirroring the data comprises,
• consulting the indexing information to determine that a corresponding cache line at another device is unavailable, and
• identifying a number of subsequent cache lines to check for availability;
• and
• completing the I/O request without mirroring the data to another device of the cache if the I/O request is a read request.

A system comprising:

• a memory operable to store indexing information for a multi-device cache for a logical volume;
• and
• a processor operable to receive an Input/Output (I/O) request from a host directed to a Logical Block Address (LBA) of the logical volume, consult the indexing information to identify a cache line for storing data associated with the I/O request, and store the data at the cache line on a first device of the cache,
• wherein the processor is further operable to mirror the data to another device of the cache if the I/O request is a write request, and complete I/O request without mirroring the data to another device of the cache if the I/O request is a read request, and
• wherein the processor is further operable to consult the indexing information to select a candidate cache line, determine that the candidate cache line is unavailable, and identify a number of subsequent cache lines to check for availability.