1. A method, with an information processing system, for reducing message flow on a message bus, the method comprising: determining if at least one logical operator in a plurality of logical operators requires processing on a given physical processing node in a group of physical nodes; pinning, based on determining that the logical operator requires processing on the given physical processing node, the logical operator to the given physical processing node, wherein the pinning prevents any subsequent reassignment of the logical operator to another physical processing node; assigning each logical operator in the plurality of logical operators to an initial physical processing node in the group of physical processing nodes on a message bus; determining if at least one logical operating in the plurality of logical operators needs to be reassigned to a different physical processing node based on a difference between a set of input message flow rates and a set of output message flow rates associated with the at least one logical operator; and responsive to determining that the at least one logical operating in the plurality of logical operators needs to be reassigned to a different physical processing node, reassigning the at least one logical operator to the different physical processing node.