We want to claim 6 in that situation. If the API claimed less than 6 on Samsung's Exynos 5 Hexa (2x A15 cores + 4x A7 cores), then the cores will be underutilized.
We already experience varying performance per core with current systems (especially mobile SoCs) using uniform core hardware, simply due to the cores being at different clocks. This does not invalidate logical processors as a measure of concurrency. Additionally, workers have no method of assigning core affinity, so the issue you bring up (cores of varying hardware performance) is already a problem in the current worker model, with or without navigator.cores. On Mon, May 5, 2014 at 11:58 AM, Boris Zbarsky <bzbar...@mit.edu> wrote: > On 5/5/14, 11:57 AM, Boris Zbarsky wrote: >> >> This doesn't really answer my question. What if there are six logical >> processors available, of which four are 10x as fast as the other two? Do >> we really want this API claiming "5"? > > > Er, I meant "claiming 6", of course. > > -Boris >