erek
[H]F Junkie
- Joined
- Dec 19, 2005
- Messages
- 10,573
Pretty unfortunate for ReBar on Linux
“The extremely low performance was attributed to AMD Smart Access Memory and when disabling the support in the BIOS, the performance improved or when running with environment variables to override the behavior. Going through this issue led well known AMD open-source Mesa developer Marek Olšák to decide on just ripping out the Smart Access Memory code from RadeonSI since it wasn't a focus and not properly tested. So rather than white/black-listing games based on if ReBAR/SAM support is helping or not, the code was just removed from this Gallium3D driver. Again, the SAM/ReBAR support does remain within the RADV Vulkan driver, which after all is more important for modern Linux gaming than OpenGL.”
Source: https://www.phoronix.com/news/RadeonSI-Drops-ReBAR-SAM
“The extremely low performance was attributed to AMD Smart Access Memory and when disabling the support in the BIOS, the performance improved or when running with environment variables to override the behavior. Going through this issue led well known AMD open-source Mesa developer Marek Olšák to decide on just ripping out the Smart Access Memory code from RadeonSI since it wasn't a focus and not properly tested. So rather than white/black-listing games based on if ReBAR/SAM support is helping or not, the code was just removed from this Gallium3D driver. Again, the SAM/ReBAR support does remain within the RADV Vulkan driver, which after all is more important for modern Linux gaming than OpenGL.”

Source: https://www.phoronix.com/news/RadeonSI-Drops-ReBAR-SAM