Stream data processing method, stream data processing program and stream data processing apparatus for runtime query group data stagnation detection and load balancing

摘要

Once data stagnation occurs in a query group which groups queries, a scheduler of a server apparatus calculates an estimated load value of each query forming the query group based on at least one of input flow rate information and latency information of the query. The scheduler divides the queries of the query group into a plurality query groups so that the sum of estimated load values of queries belonging to one query group becomes substantially equal to the sum of estimated load values of queries belonging to another query group. The divided query groups are reallocated to different processors respectively. Throughput in query processing of stream data in a stream data processing system can be improved.