Okay, well I can't understand kernel goings-on well enough to determine where said synchroni(s|z)ation mechanism lives... So we'd have to wait for Mark Lord's input on the situation. And since Mark is working on sleds right now, I wouldn't want to disturb him (well, at least not until I get my sled ). So if I can't find an acceptable solution on my own, I'll just release my program with whatever it's got, and save this for another day.