Workflow Execution: The Value Store


The Value Store is a data structure owned and maintained inside each WorkflowExecutionActor (see Major Actors).

Its purpose is to hold the set of values produced by the workflow so far. If the WOM graph holds a static representation of the workflow which doesn't change as the workflow is run, the Value Store records the values assigned to every task output and value definition evaluated so far during workflow execution.

Note: The Value Store does not hold the execution status of the various nodes in the WOM graph. Nor does it determine when downstream nodes are ready to run. That is the domain of the Execution Store.

Data Structure

The Value Store data structure is a mapping from output ports on WOM GraphNodes (and shard index if necessary) to the appropriate WomValue.


Some worked through examples of how the Execution Store and Value Store change as workflows progress are given on the Execution and Value Store Examples page.