Application-transparent hybridized caching for high-performance storage
Systems, apparatus, and computer-implemented methods are provided for the hybridization of cache memory utilizing both magnetic and solid-state memory media. A solid-state cache controller apparatus can be coupled to a host computing system to maximize efficiency of the system in a manner that is transparent to the high-level applications using the system. The apparatus includes an associative memory component and a solid-state cache control component. Solid-state memory is configured to store data blocks of host read operations. If a host-read operation is requested, the controller communicates with a solid-state cache memory controller to determine whether a tag array data structure indicates a cached copy of the requested data block is available in solid-state memory.
1. A method for hybridizing cache memory having at least one magnetic media and at least one solid-state media, the method comprising:
receiving a read request to retrieve a data block;
checking whether the at least one solid-state media is available to fulfill the read request;
when the at least one solid-state media is able to fulfill the read request, completing the read request without utilizing the magnetic media; and
when the at least one solid-state media is unable to fulfill the read request, substantially simultaneously performing both of the following:
(1) completing the read request at the at least one magnetic media; and
(2) updating the solid-state media with the data block retrieved from the at least one magnetic media.
2. The method of claim 1 , wherein the at least one solid-state media is a non-volatile memory.
3. The method of claim 1 , wherein the request includes at least a LBA number and an operand size that denotes the size of a data block request.
4. The method of claim 1 , wherein a data block is returned by a disk array controller in response to the read request.
5. One or more hardware computer-storage media devices having computer-executable instructions embodied thereon that, when executed by a computing device, perform a method for hybridizing cache memory of a serving computer system, the method comprising:
receiving, at a Redundant Array of Inexpensive Disks (RAID) storage controller in communication with at least a solid state cache control logic component and an associative memory component, a request for a hosted computing operation to retrieve a data block;
consulting a memory array associated with a cache memory component, by the storage controller, to determine if a cache hit or cache miss occurred:
when a cache hit occurs, determining, by a solid-state cache memory controller, if the request is for a hosted-read operation or a hosted-write operation, wherein if the request is a hosted-read operation, retrieving the data block from a solid-state cache memory component; and
when a cache miss occurs, determining, by the solid-state cache memory controller, if the request is for a hosted-read operation or a hosted-write operation, wherein if the request is a hosted-read operation, retrieving the data block from a magnetic-disk memory component, and completing the hosted-read operation request and copying the data block to the solid-state cache memory component on a first read access operation.
6. The media of claim 5 , wherein the solid-state cache memory component is located remotely from the solid-state cache control component.
7. The media of claim 5 , wherein the solid-state cache memory component is a non-volatile memory.
8. The media of claim 5 , wherein one or more additional solid-state cache memory components can be added without disruption to the host computing system.
9. The media of claim 5 , wherein the solid-state cache controller is one of an external controller communicating with the storage controller, an embedded component within the storage controller, or a controller within a plurality of controllers manipulated by a centralized controller.