Dual core and quad core processors are all the rage at the moment and both companies are advocating the need for these new processors as according to their marketing departments two processors can do more than one, and four … well, you get the point. But at the risk of repeating myself, although some things obviously need repeating, don’t expect to see any major leaps in performance from these. Two cores don’t mean twice the performance, nor do four cores quadruple the performance. Confusing? Not really, just a different game altogether, a few years ago things were clear-cut and obvious, every increase in processor clock speed equaled better performance, or rather all software would automatically take advantage of the faster execution. So basically more MHz meant more performance, simple really.
Not today though, you’d think that two processor cores running side by side would surely be faster than a single core right? And four cores working simultaneously would certainly run circles around it? Well no, only if the application that you are running is multithreaded and thus can take advantage of the extra cores, remember that about 99% of all software available today is programmed to run on a single core processor. Hence isn’t multithreaded and thus in the vast majority of cases you won’t see a speed up, as the second, third or fourth core is just sitting there idling, or handling simple operating system tasks that don’t eat up a lot of processing power in the first place. But wait a minute, you must have that backwards, dual and quad core processors speed up your operating system considerably and hence overall performance goes up. Well, no again, if running the operating system was such a resource hog and would eat up heaps and heaps of CPU-cycles then the difference between a 1GHz Pentium III and a 3GHz Dual Core processor would be astronomical wouldn’t it, well, rest assured, it isn’t.
So what’s needed to get these dual and quad core processors to offer genuine leaps in performance and make us forget about single core processors altogether? Well, basically the same thing that needs to happen with 64-bit support: software needs to be written, or a whole lot less likely, rewritten, to take advantage of these extra cores. And most software we use today, that includes your favorite browser, email client, etc. is not going to see much of a speedup, if any, from these optimizations. No, for dual and quad core processors to show their strengths you need some heavy applications that can benefit from parallel execution such as video and photo editing software, games, simulation and CAD/CAM software, etc. Don’t expect the mundane office applications most of us use during the day to run any faster though. So without software support dual and quad core processors simply are not going to shine, they’ll just be a novelty.