Parallel search: System-level programmin details

[AlvaroBegue]

After gathering some information here (thanks for the responses) and reading about C++11 threads, my current plan is to use a std::condition_variable where all idle threads will wait for work. After I make a split point available I will call notify_all(). That should make every idle thread go and try to grab a move to work on.

Of course, there are many details to iron out, but I think this scheme should be workable. Calling notify_all on a std::condition_variable that has no workers on it is pretty fast (22 ns according to a simple synthetic test).

If you think this is a terrible idea and have a much better suggestion, it would be appreciated. If not, I'll report back after I get something working.