IE9 SunSpider oddness prompts Microsoft benchmark-gaming rumors

Unusual testing results have led to speculation that Microsoft's Internet Explorer 9 engineers are building the browser to return unusually high benchmark results, unwarranted by overall performance. Mozilla coder Rob Sayre noticed that IE9 consistently managed a score at least 10x faster than every other browser on SunSpider's math-cordic test; he tweaked a few variations into the test (which should all have roughly the same results), and found that the performance boon only applied in the default SunSpider benchmarking.

In fact, where IE9 managed the standard math-cordic test in an impressive 1.0ms, when the tweaked versions were introduced it delivered scores around 20x slower. Similar tweaks to Chrome and Opera produced consistent results, as was expected.

Digitizor suggests that Microsoft has either optimized IE9 to return strong SunSpider results – which they say is "cheating" – or that the company's engineers have been focusing too greatly on the benchmarking test and have over-optimized the JavaScript engine to suit its requirements. Alternatively, it could be a legitimate bug, and indeed Sayre has filed a bug form on Microsoft Connect.

[via Slashdot]