1. Performance Counter.
Get vram size allocated to & used by python.exe from pdh.dll.
Generation can be slower than atiadlxx.
Use memory less greedy then atiadlxx.
Windows only.
2. atiadlxx.
Get max vram size and available vram size from AMD GPU driver (atiadlxx.dll).
Use memory more greedy than Performance Counter.
Windows & WSL are supported.
3. None.
Assume available vram size is 8GB.
Use memory regardless of current vram usage.
