(Android) Unity got Poor CPU Performance compared with Native apk
Hello everyone, my team have been contributing to develop " view dependent media player ", which using a single thread decode 2048 * 1536 with android-media-codec (we can call it BASE TEX) and four thread decode 512 * 256 * 24 split blocks for viewer directly look at with ffmpeg (we can call it HD TEX), very similar with VR_5K_PLAYER. The above main framework make the cpu usage more heavy compare with gpu. Cpu need decode 2048 *1536 totally and upload YUV from memory to video memory every frame, while gpu only decode 2048 *1536. After a few test with Samsung S8 & Quest, i found that, s8 & Quest got different performance which s8 got a high fps because of Quest has less cpu avaliability compare with S8. ( PS: S8 & Quest all equiped with snapdragon 835. as far as i know, the 835 chip contain 8 core, 4 core of all 8 core are big core responsible for heavy work ) To confirm my point of view , i made a test proj using unity & the latest gear sdk, add heavy cpu work for some thread public class NewBehaviourScript : MonoBehaviour { // Use this for initialization void Start () { for (int i = 0; i < 8; i++) { ThreadStart method = () => threadWork(); Thread thread = new Thread(method); thread.Start(); } void Update() { long sum = 0; for (int i = 0; i < 1000000; ++i) sum = (int)((sum + i) * 2.0f / 2.0f); } void threadWork() { while (true) { long sum = 0; for (int i = 0; i < 100000000; ++i) sum = (int)((sum + i) * 2.0f / 2.0f); Debug.LogFormat("TestThread End name:{0} curr thread id:{1} cur timeStamp:{2}", sum, Thread.CurrentThread.ManagedThreadId, DateTime.Now.ToString()); } } } the enclosed python file use "adb shell cat /proc/stat" to calculate 8 core usage. the above result is S8, the last four core are big core usage, while 3 big core execute full load. the above result is Quest, the last four core are big core usage, while 2 big core execute full load. my team also made a native android project which using gradle & android studio & without gear, loading my dynamic library through jni & execute view dependent media player. the S8 cpu usage is the below result is executed with S8 using unity & gear & same dynamic library, the two test show that native apk get a better & average cpu usage while heavy cpu work executing, compared with unity & gear apk. My question is, Is there a way for unity & gear apk to control device cpu availability rate ? why native apk performance diff with unity & gear apk? why Quest got less core to execute cpu work compared with S8?
