Tracking data availability using heartbeats

A computer program product for tracking replication state and providing quorum visible retrievals, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause the processor to:

• assign, by a writer node performing write operations, a sequence number;
• replicate, by the writer node, the sequence number with a write operation to other replica nodes in an asynchronous fashion thru a first network channel;
• communicate, by the writer node, a state of a local system on a second network channel by sending a latest sequence number available that has been hardened to the other replica nodes;
• obtain a query, by a reader node, and selecting a sequence number limit;
• and
• return, by the processor, results up to the sequence number limit.

An apparatus comprising:

• a memory configured to store instructions;
• and
• a processor configured to execute the instructions to:
• assign, by a writer node performing write operations, a sequence number;
• replicate the sequence number with a write operation to other replica nodes in an asynchronous fashion thru a first network channel;
• communicate, on a second network channel, a state of a local system by sending a latest sequence number available that has been hardened to the other replica nodes;
• obtain a query, by a reader node, and selecting a sequence number limit;
• and
• return results up to the sequence number limit.