We have seen the exponential growth of Android Smartphone market like no other, and the general marketing strategy has been focusing on the terms like more cores, more RAM and faster performance. But does more cores mean more speed? Is octa core better than quad core? Here's the break down.
|Quad core vs Octa Core|
Is octa core better than quad core?Broadly speaking, core are the basic computing unit in either phones or computers and are required for all the processes taking place. So it implies that if there are more cores than there can be more task done. Simple as that. But how does Apple with just two cores in the iPhone 6 manage to have a better performance than most of the Android phones with quad core and even octa core? Even the iPhone 7 has "Only" two cores compared to Android phones with Hexa core, Octa core and even Deca core. As a user main factor we need to focus on is performance and not the technical details like cores or frequency or RAM.
From the above statements we can conclude that it's not the core count that matter, or else Apple iPhones would not be near any the performance of any Android phones much less outperform them.
so what defines the performance of a device is not core count?
Simply speaking it's not the core count that matters, but how much work can a single core do. A simple and rather stupid but easy to understand analogy here, can two bodybuilders lift more or two skinny guys? It's more or less the same thing. For example, here's the benchmark result of iPhone 6 with Samsung note 4 and HTC desire 820.
|Dual core vs Quad Core vs Octa core|
Digging deeper we can find that the performance depends more on other factors than just core count and speed (frequency) of a processor chip. Some overlooked but more important aspect are memory bandwidth and ability to execute threads in a more efficient way. This governs the IPC of a chip. Simply stated IPC is "the average number of instructions executed for each clock cycle". Another stupid but simple analogy is, if you need to transfer the water from one water tank to another water tank using buckets, how much water can you carry at once and how much water a pro body builder can carry at once. Here, the amount of water you can carry at once is analogous to the average number of instructions executed per clock cycle.
The reason why the performance of the dual core processor in the iPhone 6 is better than most quad core and octa core Android phones of that time is because the processor chip in was the best mobile chip in the world at that time. Now it's the same with the processor in the iPhone 7. While the prime chip maker for Android "Snapdragon" has rolled out snapdragon 835, it's flagship for Android phones with 8 cores, 4 running at 2.4 GHZ and the other 4 running at 3 GHZ, iPhone is just sticking to better performing 4 cores.
So what the idea behind Android chip maker increasing core count? In my opinion, one factor is that they focused more on increasing the core count in the beginning even though it didn't matter much because it sounds sexier. More cores is wrongly associated with better performance. And the other factor is battery consumption. Android chip makers still are creating chips that are power hungry. So if the power of a core is increased, it would adversely affect the battery life. Hence the low powered single core and multiple instances of them. A new architecture call the big.LITTLE architecture was released in 2011 where four low-power Cortex-A7 cores are coupled with four high-performance Cortex-A15 cores. ARM has improved this setup every year since, and now are providing more capable chips on both the halves of the octa-core divide. Apple on the other hand has focused on both the power and energy efficiency of their chips and have found a "perfect" intersection of performance and efficiency.