On Tue, 2012-11-20 at 12:39 +0000, Chris Redpath wrote:
Hi Tixy,
I can now reproduce it with MMC too, and the times are pretty much the same for me :(
There is definitely some interaction with CPUFreq, the A7s stay at a low enough OPP that the busy threads during boot are never able to accumulate enough load to migrate up to an A15. Normally, it makes no sense for a thread classified as 'heavy' at 350MHz to move to an A15 since it may very well not be a heavy thread at 1GHz. This is the expected behaviour of the patch, to bring HMP migration in line with cpufreq DVFS changes.
Do you always use the ondemand governor in Linaro?
That is how I was told by people at ARM to configure vexpress for big.LITTLE MP; A15's as 'perfomance', A7's as 'ondemand'.