Tests Show Win XP Still Fastest for Multicore

When Windows XP launched in 2001, the hardware that the OS was designed to run on was far more modest. If you wanted to run a system with multiple cores, you’d have to buy a separate CPU for each core plus the expensive motherboard to go along with it. Today, cores are multiplying.

For multicore computing to really be worthwhile, software must be coded with it in mind. With dual and quad core chips being more of a modern day thing, one could assume that newer versions of Windows would be better at taking advantage of symmetrical multiprocessing (SMP) systems. Well, yes and no.

Tests conducted by InfoWorld show that Windows XP is still the overall performance king even in today’s quad core PCs. Not only does Windows XP outpace Windows Vista, it also does better than the current Windows 7 beta.

InfoWorld detailed: “If you take the raw transaction times for the database and workflow tasks, then factor them against the average processor utilization for these same workloads, you see that Windows XP consumes roughly 7.2 and 40.7 billion CPU cycles, respectively, to complete a single pass of the database and messaging workflow transaction loops on our quad-core test bed. By contrast, Windows Vista takes 10.4 and 51.6 billion cycles for each workload, while Windows 7 consumes 10.9 and 48.4 billion cycles.”

From the test, quad core systems with newer Windows ran database tasks and workflow tasks 40 percent and 20 percent less efficiently, respectively. It’s not that Windows Vista or 7 are hogs as much as XP having fewer things to deal with. Besides just visual effects, the newer Windows have to deal with extra DRM concerns. It takes overhead to support more features, and Vista is a much more secure operating system than XP.

Windows XP is leaner, and thus explains its greater efficiency. But that advantage will lessen as our CPUs gain more cores. Windows XP’s SMP implementation is more basic than the one in Windows Vista and 7, which feature tweaked kernels that take advantage of today’s multicore chips rather than just acknowledging the presence of a separate processing unit.

The theory is that as the improved multicore support of the newer Windows versions become more apparent as core count increase. The key question is where exactly (or how many cores) the newer Windows with its added bulk will surpass the leaner but less optimized XP.

While Windows Vista may have arrived before it was fully ready, Windows 7 looks to right all the wrongs and shine things back up for Microsoft. Early impressions of Windows 7 are all overwhelmingly positive, benchmarks of the beta already put it ahead of Vista. Now all we need is a fully optimized final version of Windows 7 and an eight or 16 core CPU to play with.

Source : Tom's Hardware US