Blazin: What is GPU and Rendering Profile GPU Graph

Aim: To know about GPU in Android 


Topic Covered:

• What is GPU
• Role of GPU
• Rendering GPU  graph
• Rendering Graph Explained 
• Color Indications and its meaning

What is GPU:

GPU is graphical processing unit in the android operating system Since from the smartphone revolution with extensive use of the graphics in the normall phone led to evolution of the GPU
It is consider as the soul of the CPU.
GPU performs the various graphical and transformation calculation so the CPU does not have to burden by these operations.
GPU is mostly available in stand alone form with chip only where CPU has multiple cores.
Most popular brands manufacturing the Nvidea's Gforce and Adreno by qualcomm.


Rendering the GPU Profiling Graph :

1. On your mobile device, go to Settings and Developer Options.
2. In the Monitoring section, select Profile GPU Rendering.
3. In the Profile GPU Rendering popup, choose On screen as bars to overlay the graphs on the screen of your mobile device.
4. Go to the app that you want to profile.

 

Rendering Graph Explained :

• After enabling the profile gpu rendering it will start to show the graph in the form of bars.
• Bar graphs will be in the colored format of blue red green where as each color signifies the time taken to render the graphics
• Vertical bar represents rendering of one frame against the time

Color Indications and its meaning :

• Blue 

The blue section of the bar represents the time used to create and update the View's display lists. If this part of the bar is tall, there may be a lot of custom view drawing, or a lot of work in onDraw methods.

• Purple

Android 4.0 and higher: The purple section of the bar represents the time spent transferring resources to the render thread.

• Red

The red section of the bar represents the time spent by Android's 2D renderer issuing commands to OpenGL to draw and redraw display lists. The height of this bar is directly proportional to the sum of the time it takes each display list to execute—more display lists equals a taller red bar

• Orange

The orange section of the bar represents the time the CPU is waiting for the GPU to finish its work. If this bar gets tall, it means the app is doing too much work on the GPU.