The technology disclosed improves existing streaming processing systems by allowing the ability to both scale up and scale down resources within an infrastructure of a stream processing system. In particular, the technology disclosed relates to a dispatch system for a stream processing system that adapts its behavior according to a computational capacity of the system based on a run-time evaluation. The technical solution includes, during run-time execution of a pipeline, comparing a count of available physical threads against a set number of logically parallel threads. When a count of available physical threads equals or exceeds the number of logically parallel threads, the solution includes concurrently processing the batches at the physical threads. Further, when there are fewer available physical threads than the number of logically parallel threads, the solution includes multiplexing the batches sequentially over the available physical threads.