By Andrew Binstock
It’s been eight years since simultaneous multithreading first appeared in popular processors, when Intel shipped it under the name of Hyper-Threading Technology. Since then, numerous companies have been trying to figure out how to get developers to leverage multiple threads on the desktop, whether in a single CPU or in the now-common multicore processor.

If you have paid no attention to this area during these intervening eight years, you have missed almost nothing—a rare assessment of any technology sector’s progress. Numerous attempts to make multiple threads easier for developers to tame met little interest and even less traction. As a result, only general directions for future advances have come into focus.

There is wide agreement on the limitations of the traditional mainline approach of manual thread management, which relies on a panoply of burdensome techniques: individual threads, mutual exclusion, locks, signals and so forth. These tools work (they are still the primary tool box), but they create situations that are difficult to develop for and, at times, nearly impossible to debug.

Full Story