On Wed, Aug 23, 2017 at 6:29 PM, R0b0t1 <r03...@gmail.com> wrote: > As an example, I am interested in characterizing the power consumption > of rendering a PDF document. I would hopefully only need to run the > renderer once.
The catch with that goal is that a) rendering a PDF is likely as much of a ram and disk intensive process as it is cpu intensive, b) the computational complexity of it is *completely* dependent on the source's complexity, and c) the actual power draw of the system will even vary based on external environmental factors. For a specific document, you could measure it by pre-loading everything into ram (so disk and ram i/o for the executable and data to process aren't factors), ensure the system is truly idle (i.e. no background processes, including scheduled tasks), take a power usage measurement (preferably with an external, physical, power meter) as a baseline, then run the process N times in a loop, and take a measurement of both the total run time and the change in power draw. From there, you can divide the run time by N, the multiply by the change in power draw, to get the result. That'll tell you roughly how much power you would draw every time you rendered that particular document, from ram, on that system, with those exact settings, in a room at roughly that temperature and humidity. That's potentially useful for profiling during optimization of a very specific workflow in controlled conditions, but it's really of questionable usefulness beyond that. -- Joshua M. Murphy
