Byte Buffers and Off-Heap Memory by Keith Gregory

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ABSTRACT:  Byte Buffers and Off-Heap Memory

In September of this year, Terracotta released BigMemory for Enterprise EHCache, promising to “defuse the GC time bomb” by “providing an off-heap cache not subject to garbage collection.” While the EHCache development team deserves kudos for this product, the technology to access off-heap memory has been a part of the JDK since 2002. That was the year that JDK 1.4 was released, and with it java.nio.ByteBuffer.

This presentation takes a closer look at ByteBuffer and its uses. It includes a rudimentary off-heap cache implementation, and discusses the issues that a real-world implementation must face. And it looks at memory-mapped files, in which the operating system makes an on-disk file looks like it is resident in memory. The presenter considers this latter feature more interesting than off-heap caches, as his company is using it to create “infinitely scalable” applications for processing traffic data.

SPEAKER BIO:  Keith Gregory

Keith Gregory has been a software professional for over 25 years, working in application areas from real-time data acquisition to massively parallel databases. He is currently a Lead Architect for Navteq’s Traffic Technology Group, working on a project to incorporate massive amounts of end-user GPSdata in the Navteq traffic model.

MEETING SLIDES

Link to speaker’s website/PDF