Mementos: system support for long-running computation on RFID-scale devices

Transiently powered computing devices such as RFID tags, kinetic energy harvesters, and smart cards typically rely on programs that complete a task under tight time constraints before energy starvation leads to complete loss of volatile memory. Mementos is a software system that transforms general-purpose programs into interruptible computations that are protected from frequent power losses by automatic, energy-aware state checkpointing. Mementos comprises a collection of optimization passes for the LLVM compiler infrastructure and a linkable library that exercises hardware support for energy measurement while managing state checkpoints stored in nonvolatile memory. We evaluate Mementos against diverse test cases in a trace-driven simulator of transiently powered RFID-scale devices. Although Mementos’s energy checks increase run time when energy is plentiful, they allow Mementos to safely suspend execution when energy dwindles, effectively spreading computation across zero or more p...

• Type: Journal
• Year: 2011
• Where: ASPLOS
• Authors: Benjamin Ransford, Jacob Sorber, Kevin Fu
• Keywords: ASPLOS 2011, Compiler Infrastructure, Msp430 Family, Programming Languages, Tight Time Constraints