| 17 Jul 2025 |
 woobilicious | oh wait I'm getting my logic wrong...But that is more confusing, I'd think llvm wouldn't disable a feature. | 02:52:43 |
 olivia | probably use_llvm is about using the llvm shader compiler middle/backend instead of the nir one | 02:57:20 |
| olivia | I suspect nobody has implemented fp8 or cmats in the llvm backend yet | 02:57:51 |
| woobilicious | Yeah I'd just think it would have feature parity, but I guess not. | 02:57:58 |
| olivia | I wouldn't expect it to, nobody likes it lol | 02:58:25 |
| olivia | I believe the intention is to remove it eventually, but I'm not very aware of what's going on with amd stuff so take that with a grain of salt | 02:58:51 |
| olivia | https://docs.mesa3d.org/drivers/radv.html#shader-compilation yeah
We still maintain an LLVM based compiler backend too, which is these days solely used for testing and hardware bringup. Users are recommended NOT to use the LLVM backend.
| 02:59:54 |
| woobilicious | Oh really? how is that related to the ACO compiler? doesn't that use llvm? | 03:00:08 |
| olivia | no ACO is NIR only | 03:00:44 |
| woobilicious | ahh my memory is wrong then. | 03:01:31 |
| olivia | (I believe the llvm backend in radeonsi predates NIR) | 03:01:33 |
| woobilicious | olivia: I think the FSR4 code just converts to fp16 manually instead of them extending the compiler to do the conversion. I guess the code is writting to use cooperative_matrix, so yeah only RDNA3...too bad I wanted slow as dogshit FSR4 haha. | 03:33:25 |
| olivia | yeah, that seems plausible (I don't know anything about the specifics of FSR4, but almost certainly it will not work without cmats) | 04:10:31 |
| olivia | oh, the fp8->fp16 lowering is happening in vkd3d-proton | 04:28:10 |
| olivia | https://themaister.net/blog/2025/05/09/conquering-fidelityfx-fsr4-enabling-the-pretty-pixels-on-linux-through-maniacal-persistence/ | 04:28:12 |
| olivia | https://github.com/HansKristian-Work/vkd3d-proton/pull/2427 | 04:28:22 |
| olivia | kinda cursed | 04:28:23 |
 K900 | In reply to @woobilicious:matrix.org
K900: your post mentions Intel-RT on non-x86, does that mean you can run Arc graphics on Arm? Always could | 04:54:28 |
| K900 | They're just PCIe | 04:54:28 |
| K900 | The RT code had some handrolled x86_64 SIMD but they got rid of that | 04:54:41 |
|  ribosomerocker joined the room. | 23:58:21 |
| 18 Jul 2025 |
 jonhermansen | Holy crap, I've really been missing out. Looking Glass performance is really good. Now if I can only figure out how to correctly isolate and pin my CPU cores... | 02:40:56 |
| jonhermansen | Is anyone doing similar things and wanna share their setup? | 02:42:39 |
| jonhermansen | I have serious problems with automatic core assignment in virt-manager with a game that is basically single core. Maybe I should simply try reducing the number (I have 16 P-Cores, so I gave 12 to the VM)
Maybe I also need hugepages
I thought KVM would be maybe 5% to 10% performance hit. The latency on the system becomes really bad and I don't know why. | 02:47:39 |
| jonhermansen | * I have serious problems with automatic core assignment in virt-manager with a game that is basically single core. Maybe I should simply try reducing the number (I have 16 P-Cores, so I gave 12 cores to the VM)
Maybe I also need hugepages
I thought KVM would be maybe 5% to 10% performance hit. The latency on the system becomes really bad and I don't know why. | 02:49:17 |
| jonhermansen | I have 144hz monitor and the latency transferring data from the GPU is very low, but I'm still trying to iron out the CPU issues in the guest.
Maybe I should switch to invoking qemu from a script or as a systemd service | 03:08:11 |
| jonhermansen | * I have serious problems with automatic core assignment in virt-manager with a game that is basically single threaded. Maybe I should simply try reducing the number (I have 16 P-Cores, so I gave 12 cores to the VM)
Maybe I also need hugepages
I thought KVM would be maybe 5% to 10% performance hit. The latency on the system becomes really bad and I don't know why. | 03:10:08 |
| jonhermansen | And for some reason, I can not use host-passthrough cpu or else the guest will crash. Even with migratable="off" | 03:10:55 |
| jonhermansen | guest is Windows 10 | 03:11:42 |
|  @haauler:matrix.org joined the room. | 14:24:28 |
