Projects / StreamCruncher


StreamCruncher is an event processor. It supports a language based on SQL that allows you to define "event processing" constructs like sliding windows, time-based windows, partitions, and aggregates. Such constructs allow for the specification of boundaries (some are time sensitive) on a stream of events that SQL does not provide. Queries can be written using this language, which in turn can be used to monitor streams of incoming events. It also provides a feature similar to materialized views. Joins and sub-queries are also supported to allow event co-relation. A database is used underneath to do the heavy lifting. Pattern matching or multi-stream correlation are also possible.

Operating Systems

Recent releases

  •  21 Nov 2007 07:38

    Release Notes: StreamCruncher is now an open source project, licensed under the LGPL.

    •  10 Oct 2007 14:01

      Release Notes: Correlation Queries (alert..when..) and Queries with just one Stream have been re-architected to perform better and do not use the Database. The RowSpec class has changed and the API accepts Java Data types instead of Database specific types. Correlation Queries can process 168,000 Events per second on a 1.8 GHz Centrino.

      •  21 Aug 2007 09:11

        Release Notes: Correlation Queries ( alert..when..) have been re-architected to perform better. "case..when.., first, distict, limit" clauses, "group by", and other Group functions are temporarily not working. OutputSession's return value is now List<Object[]> instead of Object[][]. A new CorrelationPerfTest test class performs a load test where four Event Streams are monitored by three different Correlation Queries.

        •  18 Jul 2007 14:57

          Release Notes: The pre-filter for input event streams now supports <, >, !=, =, *, /, +, -, "in (..)", "not in (..)", "and", and "or". The "in" clause can refer to an SQL sub-query. Such sub-queries are cached by the kernel to improve performance. An additional property, cacherefresh.threads.num, can be configured to specify the number of sub-query cache processing threads to use. Two new test cases have been added to test the new features: H2StartupShutdown3Test and ThreeEventOrderTest.

          •  04 Jul 2007 18:04

            Release Notes: This version is the result of a major refactoring job. The API has been greatly simplified. The internal architecture has changed considerably, resulting in a vast improvement in performance. The TimeWindowFPerfTest (single Query on a Stream) can do 25,500 events per second on a 1.6 GHz Centrino.


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