Yes, I'm quite convinced that it will be fine to do (noticably) longer than that too. The only basic type that holds more than 1 million is a 32-bit integer, so there's no point in artficially restricting to below that . Try sleeping for 20 or 200 seconds and see if that works, just for the fun of it (why not write a little application that takes a number of milliseconds to sleep, and try a few different things out).