While chip makers like Mediatek have just announced that they're making true octo-core chips, and HiSilicon Technologies, one of Huawei's businesses, is also working on one, it doesn't seem like too many smartphone or tablet manufacturers are eager to get one, as DigiTimes is reporting.
While Samsung's Exynos 5 Octa CPUs have been adopted by some models of Samsung's Galaxy S4 family, most chipset suppliers have not yet decided to enter the 8-core segment, revealed the sources.
Samsung's Exynos 5 Octa is not even a real octo-core chip, since it's using only 4 cores at any given time, although it could be if Samsung enabled it to be one in the future. However, probably even Samsung sees that 8 core chips would give them little to no benefit. We may see true heterogenous computing in the future that takes advantage not just of many more CPU cores than the 8 we're talking about now, but also of GPU cores, accelerators and so on.
This should start getting easier when there's mass adoption for the recently released OpenCL 2.0 standard, which probably won't happen for a couple of years, but even then we're just going to scratch the surface regarding the benefits we get out of heterogenous computing. Using heterogenous computing is not just like flipping a switch, and then you have it on. It's harder to program for it, although AMD and ARM and working hard to make it as easy as possible for developers going forward. But again, it's going to be years before any sort of significant adoption happens.
So then it's no surprise that smartphone makers are not rushing to use 8 or more CPU cores, unless they intend to lie to their customers that 8 cores chips really do bring a huge benefit over 4 core chips, when in fact it doesn't right now.
Even today, quad-core chips barely use all of their cores, except for some heavily multi-threaded apps, and Google has started taking advantage of extra cores to handle some parts of the UI, so not all of the work is done by the main CPU cores. For example, I think at this point they make it so a live wallpaper uses its own core (until it's needed by something else of course), instead of using the main one or two cores that are busy with opening applications or other parts of the UI. It will be a while until 4 cores start feeling like a bottleneck for performance in smartphones or tablets.