Processing program to rearrange order of task in stream processing

A non-transitory computer-readable storage medium having stored an information processing program causing a computer to perform a process comprising:

• acquiring, from a memory, a plurality of patterns of a plurality of tasks to be candidates of an arrangement order of the plurality of tasks from upstream to downstream of a first stream in a case of executing the plurality of tasks using a stream processing format;
• specifying, from the memory storing task information, for a pattern of the plurality of acquired patterns, an amount of data to be reintroduced to the first stream, through a second stream outside of the first stream, from one task of the plurality of tasks to another task of the plurality of tasks located upstream side of the first stream with respect to the one task;
• and
• determining, from among the plurality of acquired patterns, a pattern that indicates a rearranged order of a plurality of tasks from upstream to downstream of the first stream, based on the specified amount of data to be reintroduced for the pattern through the second stream.