Garbage collector assisted memory offloading for memory-constrained devices

Our everyday lives are becoming increasingly filled with mobile devices of varying capabilities. The common practice of creating multiple versions of the same application to cope with diverse device resource capabilities increases software development and maintenance costs. We discuss an offloading method to mask out the memory constraints on devices running a typical Java virtual machine. The method allows the garbage collector to selectively offload part of the object heap into a nearby wired server. In comparison with traditional virtual memory techniques, the garbage collector can make wiser offloading choices using information about object access patterns at a finer granularity. Our experiments show that our prototype introduces modest overhead in the JVM while allowing applications to execute on devices without enough physical memory. In addition, when running with the Linux virtual memory system under intense memory constraints, the prototype achieves an average improvement of 24% in run-time performance and 53% in energy savings.