On Mar 27, 2014 2:32 AM, "Matt Thomas" <m...@3am-software.com> wrote: > > > I recently ordered an ODROID-XU Lite to help beat on the my ARM MP code. > > However, it has a quirk that I don't think our scheduler will deal with. > > It has 4 Cortex-A15 cores @ 1.4Ghz and 4 Cortex-A7 cores @ 1.2Ghz. Even if the frequencies weren't different, the A15 cores at least twice as fast per cycle than the A7. That asymmetry is going to cause havoc with the scheduler. In terms of power, the A7s use a lot less than the A15s so if you can keep the work on the A7s and leave the A15s sleeping, you'll extend your battery life a lot.
Yes these things are odd. Haven't got one yet. I did see that GCC now has a dual optimization mode for code that nerds to run on both. There are a few research documents around on what works for scheduling. Justin
