Candidate set solver with user advice

摘要

A stream application uses small chunks of executable code configured to process data tuples flowing into a processing element. A scheduler allocates the processing elements to individual compute nodes or hosts for execution. However, the stream application may assign various constraints that stipulate which hosts are suitable for a particular processing element. If a host meets the constraints, it may be categorized as an unconditional candidate host. In addition, the scheduler may also track conditional candidate hosts that would be suitable for the processing element if a certain user action is performed—e.g., modifying a constraint, removing a constraint, modifying a stream element, and the like. The list of conditional candidate hosts may then be displayed to the user who can choose to perform the one or more actions to change the conditional candidate host to an unconditional candidate host for the processing element.

主权项

1. A computer-implemented method for allocating a processing element selected from a plurality of processing elements to one of a first and a second compute nodes, computer-implemented method comprising:
prioritizing for display an indication of the first compute node and an indication of the second compute node based on respective total number of unsatisfied constraints associated with the first and second compute nodes, wherein the respective unsatisfied constraints are selected from a plurality of constraints in a constraint tree; associating the first compute node and the second compute node with respective user actions, wherein each user action at least one of: (i) changes a condition such that the associated compute node satisfies an unsatisfied constraint and (ii) instructs that the unsatisfied constraint of the associated compute node be ignored; upon determining the first and second compute nodes satisfy at least one constraint in the constraint tree, transmitting for prioritized display the indication of the first compute node and the associated user actions and the indication of the second compute node and the associated user actions; and responsive to the user performing at least one of the respective user actions, allocating, by operation of one or more computer processors, the processing element to the first or second compute node associated with the performed user action.