Cache sharing in virtual clusters

1. A method, comprising:

receiving, by a processor operating in a computing node, a disk block associated with a hard disk drive, the computing node associated with a cluster in a virtual computing environment;

determining, by the processor, a local random-access memory operating in the computing node is unavailable for a storage of the disk block;

transferring, by the processor, the disk block to a cluster neighbor cache operating in a neighbor node associated with the cluster in the virtual computing environment, the neighbor node establishing the cluster neighbor cache as a shared resource for the storage of the disk block associated with the cluster; and

adding, by the processor, an entry to an electronic database that logs the transferring of the disk block, the electronic database electronically associating the cluster neighbor cache to the disk block and to the neighbor node as a destination machine;

wherein the cluster neighbor cache remotely stores the disk block in response to the local random-access memory being unavailable.

2. The method of claim 1 , further comprising retrieving the disk block from the cluster neighbor cache operating in the neighbor node associated with the cluster.

3. The method of claim 1 , further comprising querying the cluster neighbor cache to retrieve the disk block from the neighbor node associated with the cluster.

4. The method of claim 1 , further comprising storing a hash value representing the disk block.

5. The method of claim 4 , further comprising electronically associating the hash value to an identifier associated with the cluster neighbor cache.

6. The method of claim 1 , further comprising electronically associating the disk block to the computing node as an origination machine.

7. The method of claim 1 , further comprising electronically associating a hash value representing the disk block to the neighbor node.

8. The method of claim 1 , further comprising polling the neighbor node for an available capacity of the cluster neighbor cache.

9. The method of claim 8 , further comprising receiving a neighbor cache report sent from the neighbor node responsive to the polling, the neighbor cache report specifying the available capacity of the cluster neighbor cache.

10. The method of claim 1 , further comprising sizing the cluster neighbor cache.

11. An information handling system associated with a cluster in a virtual computing environment, the information handling system comprising:

a processor; and

a local random-access memory accessible to the processor, the local random-access memory storing instructions that when executed cause the processor to perform operations, the operations comprising:

receiving a disk block associated with a hard disk drive;

determining the local random-access memory is unavailable for a cache storage of the disk block;

transferring the disk block to a cluster neighbor cache operating in a neighbor computing node associated with the cluster in the virtual computing environment, the neighbor computing node establishing the cluster neighbor cache as a shared resource for the cache storage of the disk block associated with the cluster; and

adding an entry to an electronic database that logs the transferring of the disk block, the electronic database electronically associating the cluster neighbor cache to the disk block and to the neighbor computing node as a destination machine;

wherein the cluster neighbor cache remotely stores the disk block in response to the local random-access memory being unavailable.

12. The system of claim 11 , wherein the operations further include retrieving the disk block from the cluster neighbor cache operating in the neighbor computing node associated with the cluster.

13. The system of claim 11 , wherein the operations further include querying the cluster neighbor cache to retrieve the disk block from the neighbor computing node associated with the cluster.

14. The system of claim 11 , wherein the operations further include storing a hash value representing the disk block.

15. The system of claim 11 , wherein the operations further include electronically associating the hash value to an identifier associated with the cluster neighbor cache.

16. The system of claim 11 , wherein the operations further include electronically associating the disk block to the computing node as an origination machine.

17. The system of claim 11 , wherein the operations further include electronically associating a hash value representing the disk block to the neighbor node.

18. A memory device storing instructions that when executed cause a processor to perform operations, the operations comprising:

receiving a disk block associated with a hard disk drive;

determining a local random-access memory is unavailable for a cache storage of the disk block;

transferring the disk block via a communications network to a cluster neighbor cache operating in a neighbor computing node associated with a cluster in a virtual computing environment, the neighbor computing node establishing the cluster neighbor cache as a shared resource for the cache storage of the disk block associated with the cluster; and

adding an entry to an electronic database that logs the transferring of the disk block, the electronic database electronically associating the cluster neighbor cache to the disk block and to the neighbor computing node as a destination machine;

wherein the cluster neighbor cache remotely stores the disk block in response to the local random-access memory being unavailable.

19. The memory device of claim 18 , wherein the operations further include retrieving the disk block from the cluster neighbor cache operating in the neighbor computing node associated with the cluster.

20. The memory device of claim 18 , wherein the operations further include querying the cluster neighbor cache to retrieve the disk block from the neighbor computing node associated with the cluster.