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Further research, I found: https://gpuopen.com/ags-sdk-5-4-improves-handling-video-memory-reporting-apus/ https://gpuopen.com/ags-sdk-5-4-improves-handling-vid

Further research, I found: https://gpuopen.com/ags-sdk-5-4-improves-handling-video-memory-reporting-apus/ https://gpuopen.com/ags-sdk-5-4-improves-handling-video-memo... Which says: "For APUs, this distinction is important as all memory is shared memory, with an OS typically budgeting half of the remaining total memory for graphics after the operating system fulfils its functional needs. As a result, the traditional queries to Dedicated Video Memory in these platforms will only return the dedicated carveout – and often represent a fraction of what is actually available for graphics. Most of the available graphics budget will actually come in the form of shared memory which is carefully OS-managed for performance." The implication seems to be that you can have an arbitrary amount of graphics RAM, which would be appealing for AI use cases, even though the GPU itself is relatively underpowered. Still, the question remains open, how to precisely control APU/GPU memory allocation on Linux and what is the limitations? https://github.com/GPUOpen-LibrariesAndSDKs/AGS_SDK/ https://github.com/GPUOpen-LibrariesAndSDKs/AGS_SDK/

Espionage724 3y ago
For Intel, there's DVMT that can be set to different values; with setup_var I can change the memory allocation for Intel UHD 630 from 256MB to 1GB. I wonder if a BIOS modification could be done to go past the 1GB limit? It sounds like the size modification has to come from the BIOS or VBIOS firmware. For Intel, some BIOS setting names that control memory usage are "DVMT Pre-Allocated", "DVMT Total Gfx Mem", "Above 4GB MMIO BIOS assignment", and "Aperture Size". If I had a platform I could re-flash the BIOS easily and had any idea what I was doing with a hex editor, I'd see if "DVMT Pre-Allocated" or "DVMT Total Gfx Mem" had an obvious memory limit number, raise it, and check lspci in Linux to see if anything happened.
- andrewstuart 3y ago
  1GB seems low.
  - Espionage724 3y ago
    I actually increase to 2GB my mistake. It's still not generally that much but seems fine as long as resolution isn't too high for games (720p seems most ideal for performance).

Espionage724 3y ago

For Intel, there's DVMT that can be set to different values; with setup_var I can change the memory allocation for Intel UHD 630 from 256MB to 1GB. I wonder if a BIOS modification could be done to go past the 1GB limit? It sounds like the size modification has to come from the BIOS or VBIOS firmware. For Intel, some BIOS setting names that control memory usage are "DVMT Pre-Allocated", "DVMT Total Gfx Mem", "Above 4GB MMIO BIOS assignment", and "Aperture Size". If I had a platform I could re-flash the BIOS easily and had any idea what I was doing with a hex editor, I'd see if "DVMT Pre-Allocated" or "DVMT Total Gfx Mem" had an obvious memory limit number, raise it, and check lspci in Linux to see if anything happened.

andrewstuart 3y ago
1GB seems low.
- Espionage724 3y ago
  I actually increase to 2GB my mistake. It's still not generally that much but seems fine as long as resolution isn't too high for games (720p seems most ideal for performance).