Does single thread application utilize multi core in android?

Question

Does single thread application use all the 4 core in a Quad-core phone. I searched this a lot and found some articles that says yes and some saying no. some articles even say the android OS doesn't utilize the 4 core.

Is android capable of using all 4 cores in an Quad core processor?

Does single thread application utilize multi core?

Answer 1

The answer is YES.

Android is basically built upon Linux kernel which does utilize mulit-core. As far as single-threaded-application is concerned, remember that a thread can not be executed in-parts on different cores simultaneously. So although your single-thread can be executed by different cores at different point in times, it can not be sub-divided and executed by different cores at the same time.

Having said that, please be aware that chipset manufacturers like Qualcomm are developing intelligent processors capable of sub-dividing your single-threaded app code (if and only if there are mutually exclusive parts) into multiple threads and have it run on different cores. Here again, the basic principle remains same - in order to utilize multi-core, the single thread was sub-divided into multiple threads.

To get the most out of your multi-core chip, you would rather create a multi-threaded app, with maximum possible asynchronous threads, so as to have optimum utilization of maximum number of cores. Hope this clears.

EDIT:

This also translates to - An app that does not make use of multiple asynchronous threads (or any other parallelism construct) will NOT use more than one core.