Today's typical desktop computer runs multiple programs at once, playing music while the user writes an e-mail and surfs the Web, for instance.

"Responsiveness really is king," he said. "This is what people want."

The problem in being responsive, he noted, is "how does the OS know [which task] is the important thing?" You don't want to wait for Microsoft Word to get started because the antivirus program chose that moment to start scanning all your files.

Most OSes have some priority scheduling to avoid these bottlenecks, but they are still crude. (Probert even suggested telemetry, in the form of a "This Sucks!" button on each computer, that a user can push whenever he or she gets frustrated with the computer's pokiness. The resulting data could be compiled to give OS developers a better idea of scheduling.)

As they began adding multiple processor cores, chip makers took a "Field of Dreams" approach to multicore chips: Build them and hope the application programmers would write programs for them. The problem is today's desktop programs don't use the multiple cores efficiently enough, Probert said.