Stories
Slash Boxes
Comments

SoylentNews is people

Submission Preview

No link to story available

Inverse multithreading on Intel Skylake CPUs?

Accepted submission by Rich https://soylentnews.org/~Rich/ at 2015-08-15 01:47:50
Hardware

German IT media house Heise reports weird benchmark results for the new "Skylake" generation of Intel Core CPUs (original report in German: http://www.heise.de/newsticker/meldung/Skylake-mit-inversem-Hyper-Threading-2779793.html [heise.de]). The tested CPU exhibited more than a factor-two speedup over the previous Broadwell generation for single-thread tasks in a specific benchmark, but the performance did not scale with more cores; it even dropped below single core performance.

With somewhat stagnating clock rates in the past few years, the path to optimization has recently been to improve the Instructions-Per-Clock rate, through widening of the execution path, and, more importantly, through improved branch predition. But with major improvements in the Sandy Bridge and Broadwell generation branch predictors, Intel had reached a point of diminishing return in this area.

Do they have an unexpected ace up their sleeves, or what explains this mystery?


Original Submission