1. T +31 20 314 0950 info@sig.eu www.sig.eu SEFLab: A Lab for Measuring Software Energy Footprints Miguel Ferreira, Eric Hoekstra, Bo Merkus, Bram Visser, Joost Visser 2013/05/20

2. 2 I 5 Help developers build energy efficient software Message Developers manage computer resources to implement some functionality. To help developers chose for energy efficiency we need to know the “cost” of using each resource. GREENS 2013 – San Francisco © Software Improvement Group

3. 3 I 5 Accurate measurement is hard Issues we dealt with Isolating components is not always easy Reduce frequency of signals to a measurable value Shield out noise from environment GREENS 2013 – San Francisco © Software Improvement Group

4. 4 I 5 Classify software activity Open issues Need to identify what is the software doing low-level technical activity: IO, processing, waiting times … high-level technical activity: DB request, file/memory access,(R/W), drawing, … functional activity: add to cart, checkout, update user data, … Need to isolate each type of activity while keeping interference to a minimum Source code instrumentation Profiling techniques Run unit tests What if the source code is not available? GREENS 2013 – San Francisco © Software Improvement Group

5. 5 I 5 Experimental design Questions for the workshop Comparative studies How to select/create a representative load? How to design experiments to achieve… architecture-level recommendations? coding-level recommendations? GREENS 2013 – San Francisco © Software Improvement Group