Speaker: Dr. Pavlos Petoumenos from the University of Edinburgh

Title: How fast? How furious? Real optimisations for real people

Abstract: Optimisation techniques depend on representative workloads for their
training, fine tuning, and evaluation. Traditional research areas have workloads
which at least try to be representative. Research on smartphones on the other
hand utilises completely inappropriate benchmarks. Typical work on the field
fails to deal with interactivity, user perception, different classes of mobile
applications, significant variation in usage patterns amongst users, and even
reproducibility. With the majority of our computing experience revolving around
these devices, it's imperative that we find ways to test our optimisations on
them properly. In my talk, I will present two novel workload creation techniques
targeted at mobile devices. Both of them are lightweight, easy to use, and
capture how real users interact with their devices. They do not require any
instrumentation, knowledge of the application's internals, or access to the
application source code. We use them to drive personalised iterative compilation
with almost no negative effect on the user experience and to show that available
ANDROID frequency governors leave substantial room for improvement, up to 27%
lower energy consumption for the same user experience.