Valmar: High-bandwidth real-time streaming data management

In applications ranging from radio telescopes to Internet traffic monitoring, our ability to generate data has outpaced our ability to effectively capture, mine, and manage it. These ultra-high-bandwidth data streams typically contain little useful information and most of the data can be safely discarded. Periodically, however, an event of interest is observed and a large segment of the data must be preserved, including data preceding detection of the event. Doing so requires guaranteed data capture at source rates, line speed filtering to detect events and data points of interest, and TiVo-like ability to save past data once an event has been detected. We present Valmar, a system for guaranteed capture, indexing, and storage of ultra-high-bandwidth data streams. Our results show that Valmar performs at nearly full disk bandwidth, up to several orders of magnitude faster than flat file and database systems, works well with both small and large data elements, and allows concurrent read and search access without compromising data capture guarantees.