Acunu Analytics runs directly on top of the open source Apache Cassandra NoSQL database. Early adopters of Acunu Analytics typically used an Acunu-supplied distribution of Cassandra because it was more robust and out-performed the standard version of Cassandra. However, the latest version of Cassandra (1.2) is more competitive in this respect, not least because of Acunu's contribution to this open source project. For example, the virtual nodes implemented in this release were contributed by Acunu. Acunu now only supports the Apache Cassandra version for new customers.
Acunu Analytics, as its name implies, is an analytics solutions for building real-time monitoring and analytic applications to run on top of Cassandra. Thus the product effectively combines a database with an analytic development environment. The way that it works is that it incrementally maintains roll-up cubes on data as it is ingested. It reflects fresh data immediately in queries on the cubes, queries that are close to instantaneous because they typically only retrieve pre-calculated results.
Acunu Analytics provides a set of aggregation functions plus associated average and variance operations; count distinct and top-k functions (with variable levels of accuracy) to show things like unique visitors, trending topics, slowest nodes or most valuable customers; and there is support for GROUP BY operators to divide events across the values in a field. It also supports automatic bucketing for time fields and hierarchical grouping to support URLs, paths and geo-spatial queries.