How Exynos 5 Octa HMP efficiently allocates workload to big.LITTLE CPU cores

Exynos 5 Octa is Samsung’s SoC processor that packs 8 ARM CPUs in a configuration dubbed big.LITTLE, a catchy phrase that describes a computing architecture whereby low-powered cores (LITTLE) are coupled with high-powered cores (big) to produce a more resource-efficient system.

In Exynos 5 Octa, there are 4 big cores (Cortex-A15 cores) and 4 LITTLE cores (Cortex-A7 cores). The big cores operate in the 1.6 GHz to 2.0 GHz range, while the LITTLE cores are in the 1.2 GHz to 1.3 GHz range.

Exynos 5 Octa 5420 is the newest model. It is the brains inside the Samsung Galaxy Note 3 and the 2014 edition of the Samsung Galaxy Note 10.1.

A feature of the Exynos 5 Octa that makes it very resource-efficient is called Heterogeneous Multi-Processing (HMP). This solution uses a global task scheduler to “efficiently allocate workload to different combinations of CPU cores.” The following videos show how the Exynos 5 Octa uses HMP to perform its magic.

Using the Angry Birds game, this video shows how the Exynos 5 Octa 5420 model uses HMP to achieve energy-efficiency.

While this one uses the QuickOffice application to demonstrate how the same processor “uses a global task scheduler to assign the right combination of CPU cores to handle each function within the app.”