recent meetings
04/18/12: "Ask Me Anything" by Eric S. Raymond
03/27/12: "URL Re-writing for the Next-Generation Web User" by Lincoln Baxter III
02/29/12: "Java Performance Monitoring" by Paul Jasek
12/13/11: "Android: Rise of the Machines!" by Frank Zammetti
10/25/11: "Java SE7 Preview" by Kirk Spadt
Keith Gregory's "Byte Buffers and Off-Heap Memory"
Sponsored by LearnQuest
ABSTRACT:
In September of this year, Terracotta released BigMemory for Enterprise EHCache, promising to “defuse the GC time bomb” by “provid[ing] 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 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 GPS data in the Navteq traffic model.
Presentation slides in PDF format here
