Dynamically configureable placement engine

A system, comprising:

• a computer processor;
• and
• a memory containing a program that, when executed on the computer processor, performs an operation for establishing a stream application, comprising:
• selecting a processing element from a plurality of processing elements in the stream application based on at least one processing element selection criteria;
• determining, based on one or more of the constraints, a plurality of candidate compute nodes to which the processing element can be allocated from among a plurality of compute nodes;
• selecting, based on at least one of the compute node selection criteria, a compute node from the candidate compute nodes,
• wherein at least one of the processing element selection criteria and the compute node selection criteria is determined by a current optimization mode for the stream application;
• allocating the processing element to the selected compute node;
• allocating each of the plurality of processing elements in the stream application;
• if the time spent allocating each of the plurality of processing elements exceeds a threshold time, changing the current optimization mode to a different optimization mode selected from a plurality of optimization modes;
• and
• restarting an allocation of the plurality of processing elements in the stream application.

A computer program product for establishing a stream application, the computer program product comprising:

• a computer-readable storage medium having computer-readable program code embodied therewith, the computer-readable program code configured to:
• select a current optimization mode for the stream application from a plurality of optimization modes based on at least one of a number of constraints, a type of each constraint, and a number of a plurality of compute nodes, wherein the current optimization mode optimizes at least one of a solvability of the stream application, a performance of the stream application, a cost of executing the stream application, and a cluster configuration of the stream application;
• select a processing element from a plurality of processing elements in the stream application based on at least one processing element selection criteria;
• determine, based on one or more of the constraints, a plurality of candidate compute nodes to which the processing element can be allocated from among the plurality of compute nodes;
• select, based on at least one of the compute node selection criteria, a compute node from the candidate compute nodes,
• wherein at least one of the processing element selection criteria and the compute node selection criteria is determined by the current optimization mode for the stream application;
• and
• allocate the processing element to the selected compute node.