the Exynos 5 Octa, the chip may not be all it’s cracked up to be.
by justfine790 • Jun 2, 2013 11:56 AM
From the Android Authority;
The Exynos 5 Octa and the State of Samsung SoCs
by Daniel Charlton
"All of this leads up to the Exynos 5 Octa and the Galaxy S4. The Octa is used in the GT-I9500 variant of the Galaxy S4 and is supposed to solve the problem of Cortex-A15 power consumption by using ARM’s big.LITTLE architecture. big.LITTLE allows the use of two core clusters, one for high-performance tasks and one for low-performance tasks. In the Octa, this is a quad-core Cortex-A15 cluster and a quad-core Cortex-A7 cluster, all built on 28nm. In big.LITTLE, there are supposed to be three modes for managing threads across all of the cores in both clusters. Evidence thus far suggests that the Octa really only supports one of these modes – the least efficient. Even worse, it appears that this limitation is due to crippled hardware in the SoC and not something that can be fixed in software"
"According to Samsung, there is no hardware problem at all and the company chose cluster-migration because it “show[s] increased performance/efficiency.” But the statement does not match up with most people’s understanding of ARM’s big.LITTLE architecture. Moreover, ARM demonstrated core-migration working on a pre-release version of the Octa. And Samsung’s released kernel source code for the Octa includes the drivers for core-migration. But that code does not work in the final release version of the Octa and Samsung has been coy in giving a straight answer. Based on this, Linus Torvalds wrote:“quite frankly, the fact that the Exynos 5 currently only works in ‘either or’ configuration almost certainly means that there is something fundamentally wrong with the hardware design, to the point where no amount of ‘complex patches’ can fix it.” While this certainly makes it seem that Samsung has done something wrong in the Octa, the chip is still entirely based on desigfrom ARM."
I have been saying since before Exynos was launched it was going to be a flop. The fact is that even Samsung realizes that it is a failure but they wan to keep their public image up so they tout it publicly. Essentially Samsung is a failure working with Microprocessors. In the end, I believe that they will get out of the CPU business. They will become a memory only chip vendor. I believe they will go to Intel for their higher end chip needs and continue to buy low end Qualcomm chips to power their phones.