GPU Memory Writes
The GPU Memory Writes metric represents the number of bytes written to GPU memory. For example, GPU memory may be used when drawing to render targets.
On Intel® HD Graphics 2500/4000: to access this metric, you must explicitly enable the Intel® Graphics Performance Analyzers option in your BIOS settings:
Select System Agent (SA) Configuration
Select Graphics Configuration
Reboot your machine
If the BIOS on your system does not include the Intel® Graphics Performance Analyzers option, update your BIOS to the latest version from Intel. After completing your performance monitoring activity, we recommend that you disable the Intel® Graphics Performance Analyzers BIOS option and reboot your machine.
If GPU Memory Writes is 640,000,000, it means 640,000,000 bytes were written to GPU memory.
GPU Memory Writes are performed by multiple graphics operations. Some ways to reduce the number of GPU memory writes include:
- Reducing the number of rendering passes.
- Reducing the number of textures in the scene.
- Avoiding overdraw, where multiple draw calls render to the same pixel. Techniques to minimize overdraw include culling and drawing objects from front to back (taking advantage of depth-testing, which can “abort” the draw call from fully executing the entire pixel shader).
To help minimize GPU Memory Writes, capture a typical frame while the game is running, use this frame as input to the Intel® GPA Frame Analyzer, and try one or more of the following techniques:
- Use the 2×2 Textures experiment (in the Experiments tab) to see if textures are a bottleneck.
- Examine the use of textures by opening the Texture tab to see the texture size, format, and mip level.
- Use the Overdraw option in the Render Target Viewer to see which pixels are written to multiple times.
This metric is always a multiple of 64, since the Intel® HD Graphics 2500/4000 performs GPU Memory Writes transactions in terms of 64-byte cache lines.