ForkJoin wakeup update

[Aleksey Shipilev]

On 10/18/2012 10:38 PM, Gregg Wonderly wrote:
>> * The main systems-level goal should be to find ways to make
>> wakeups faster. Possibly entailing support of some sort of bulk
>> signalling facilities?
> Might there be some opportunity to use a PID mechanism here so that some
> amount of dynamic tuning might happen automatically?

I've played with these a bit back in the days.

While sounding good in theory, they fail to account warmup effects
properly, and especially are bad with non-linear behaviors (which is the
usual behavior for general application under resource constraints).
Maybe it would help in pathological cases though.

-Aleksey.