Not sure if this is a me problem or a game problem, broke suddenly without any changes to my environment, and I can confirm it's still broken even after updating to a newer ProtonGE and copying in/symlinking the latencyflex files.

DXVK_NVAPI_DRIVER_VERSION is set to '49729', reporting driver version 497.29
222.024:0134:0138:trace:loaddll:build_module Loaded L"C:\\windows\\system32\\latencyflex_layer.dll" at 00000000878E0000: builtin
222.025:0134:0138:trace:loaddll:free_modref Unloaded module L"C:\\windows\\system32\\latencyflex_layer.dll" : builtin
222.025:0134:0138:fixme:virtual:NtQueryVirtualMemory (0xffffffffffffffff,0x878e0000,info_class=3,0x7cd3c0,48,(nil)) Unknown information class
Loading latencyflex_layer.dll failed with error code: 1114
NvAPI_Initialize: OK
NvAPI_QueryInterface (0x33c7358c): Unknown function ID
NvAPI_QueryInterface (0x593e8644): Unknown function ID
NvAPI_D3D_SetSleepMode: No implementation

Looking through the code I notice you wait for the OS scheduler to wake on time and then begin the frame.

The problem with this model is the accuracy of the OS thread scheduler.

Blocks the execution of the current thread for at least the specified sleep_duration. This function may block for longer than sleep_duration due to scheduling or resource contention delays. The standard recommends that a steady clock is used to measure the duration. If an implementation uses a system clock instead, the wait time may also be sensitive to clock adjustments.

I would suggest we wake early using some sort of bias and then spin checking the clock until we meet the deadline.

I'm just setting up a dev environment now. :)

Checked everything according to the guide. https://github.com/ishitatsuyuki/LatencyFleX/blob/master/docs/TROUBLESHOOTING.md At the end of the log file is :

../builtin.cpp: Querying MemoryWineUnixFuncs failed c0000135
../builtin.cpp: Look for library loading errors in the log and check if liblatencyflex_layer.so is installed on your system.

latencyflex_layer.so is in /usr/lib/wine/x86_64-unix/ and /usr/lib64/wine/x86_64-unix/, and liblatencyflex_layer.so is also in /usr/lib/

Trying to enable the middleware on Apex Legends, but game doesn't seem to allow me to enable it.

What I've done, have I missed anything?

• Installed latencyflex and latencyflex-wine
• Copied nvapi.dll64 to steamapps/common/Proton - Experimental/files/lib64/wine/nvapi/
• Added dxvk.conf to steamapps/common/Apex Legends/ as described in README
• Symlinked latencyflex_layer.dll and latencyflex_wine.dll from /usr/lib/wine/x86_64-windows/ into steamapps/compatdata/1172470/pfx/drive_c/windows/system32/
• Added launch parameters PROTON_ENABLE_NVAPI=1 DXVK_NVAPI_DRIVER_VERSION=49729 DXVK_NVAPI_ALLOW_OTHER_DRIVERS=1 LFX=1 %command%

Full Log (with DXVK_NVAPI_LOG_LEVEL=info).

System: Arch Linux 5.16.10 GPU: Radeon RX590 Driver: Mesa 21.3.6

Currently LatencyFleX has all the appropriate build files in layer/, however this can be a bit weird for packagers like Flatpak as ideally they would use something along the lines of buildsystem: meson and that'll handle most everything. This isn't the case, and it can complicate the build process a bit.

As of 6 days ago, Deep Rock Galactic supports Nvidia Reflex.

However, I enabled LatencyFlex, and once I click "continue" on the initial loading screen, the game freezes and crashes during the "initializing" splash screen while loading into the spacerig. Disabling Mangohud causes the crash to go away, but Nvidia Reflex is still greyed out in-game, despite having it working with the same launch options and same proton version as Apex, where it is working fine.

The option stayed greyed out no matter if I selected DX11 vs DX12, fullscreen vs borderlerss windows, fps cap enabled vs disabled, etc. V-sync was disabled for all testing.

I know it's not a competitive game, so reflex isn't too necessary, but still neat that another linux game has it.

I'm having Mangohud from "custom-metric" branch installed and working.

If Nvidia Reflex is enabled in game, I can see the latency graph (the green line) and latency values (actual numbers) both updated in real time. But if Nvidia Reflex is disabled, only the graph (green line) remains working real-time, while the latency numbers displayed are stuck to the last whatever values they had when NR was enabled. Ideally I'd like to see the latency values still displayed and updated real-time even when NR is not enabled, so I could compare the latencies in both situations. I'm not sure if this is a bug, or something not implemented.

Hello, hope you're doing well. I've managed to successfully install LatencyFleX for Overwatch 2 but for some reason Apex Legends has been giving me a some trouble.

Troubleshooting steps taken

• I have triple checked that I installed everything correctly from the install instructions
• I have gone through the troubleshooting step and nothing has been applicable up until "Checking if the Wine bridge successfully initialized" I see that Loading latencyflex_layer.dll failed with error code: 1114 except unlike the troubleshooting steps guide, the only error code appears to be some unrelated NvAPI_QueryInterface:

Snippet of log file DXVK_NVAPI_DRIVER_VERSION is set to '49729', reporting driver version 497.29 1326.498:0128:012c:trace:loaddll:build_module Loaded L"C:\\windows\\system32\\latencyflex_layer.dll" at 0000000058850000: builtin 1326.498:0128:012c:trace:loaddll:free_modref Unloaded module L"C:\\windows\\system32\\latencyflex_layer.dll" : builtin Loading latencyflex_layer.dll failed with error code: 1114 NvAPI_Initialize: OK NvAPI_QueryInterface (0x33c7358c): Unknown function ID NvAPI_QueryInterface (0x593e8644): Unknown function ID NvAPI_D3D_SetSleepMode: No implementation

Please note that I have verified that both liblatencyflex_layer.so and latencyflex_layer.so have been installed correctly. Furthermore I haven't used a single symlink, every file has been copied manually to its respective install directory.

Some info that may be of relevance

• I am using Proton-GE as opposed to Valve's proton
• Proton-GE is installed onto my main drive, while Apex is installed on a separate drive
• Proton-GE is up to date, so NVAPI v0.6 is installed

Please let me know if there is anything else I can provide to help out. Full log file is attached bellow. steam-1172470.log

Installed LFX from AUR and was fighting to get it to work for hours. Decided to start from scratch and just manually install everything. When I downloaded the files from repo I noticed that the file sizes were dramatically different. latencyflex_layer.dll from AUR was 50B but my manual download was 189.2KiB and my latencyflex_wine.dll from AUR was 49B while my manual download was 30.8KiB just as an example. Other files had the same discrepancy, not 100% sure what the issue is with AUR. I can recompile and provide the files if necessary.

The readme instructions for setting up the UE4 Hook offset say to run this command: readelf -Ws PortalWars/Binaries/Linux/PortalWars-Linux-Shipping.debug | c++filt | grep FEngineLoop::Tick

However, PortalWars-Linux-Shipping.debug does not exist for me. PortalWars-Linux-Shipping does though. When running this command on PortalWars-Linux-Shipping, it returns nothing. However, running readelf -Ws PortalWars/Binaries/Linux/PortalWars-Linux-Shipping | c++filt | grep FEngineLoop (without the ::Tick on the end) returns:

10585: 0000000000ae11c8 56 OBJECT GLOBAL DEFAULT 11 vtable for FEngineLoop.

Running readelf -Ws PortalWars/Binaries/Linux/PortalWars-Linux-Shipping | c++filt | grep Tick (without the FEngineLipp on the end) returns an extremely large amount of variables, and running it with ::Tick or ::tickalso returns nothing.

Would ae11c8 be the offset then? I'm concerned about the absence of the .debug extension in the file name, and concerned about the absence of the ::Tick() extension in the readelf... command.

Also, is there no concern over getting banned in Splitgate for using UE4 Hooking? Splitgate, even on linux, uses EQ8 anti-cheat. However, in the table of tested games in the readme, only Apex and Overwatch have anti-cheat warnings on them -- not Splitgate. Is there a reason these games have this warning, but Splitgate doesn't?

Next release of Northstar will support this. The original title never supported Nvidia Reflex, so this is a "native" implementation of LatencyFlex using the wine extensions.

It is my understanding that a decrease in FPS is to be expected with the feature enabled, but the difference I see is unexpected. To illustrate I measured the FPS in identical game scenarios using at first uncapped FPS, followed by capped at 80 >70 > 60 and finally again uncapped but with Nvidia Reflex enabled.

The first section uncapped is averaging around 100 FPS, but is clearly all over the place, while the following capped sections are much better, especially the one at 60 FPS. The Reflex-enabled one is puzzling because not only its roughly half of the initial FPS, but subjectively (and in the graph) seems rather rougher than what I expected.

My questions would be: Is this significant difference to be expected, or maybe is something wrong in my setup/testing? Is there any option to compromise between reducing latency and assuring a minimal FPS, as in: "do what you can, but don't go below 60 FPS"?

Related to https://github.com/ishitatsuyuki/LatencyFleX/issues/3, as Windows support would benefit game engines that don't wish to link against the proprietary NVIDIA Reflex SDK.

The README mentions:

For now, LatencyFleX can be used on Linux through one of the following injection method. Game engine integration is planned.

Out of curiosity, do you have any idea how this could be implemented? I'm interested in seeing if adding support for LatencyFleX within Godot could be possible in the future :slightly_smiling_face:

While I am playing Overwatch and Apex Legends, there are times where I will be getting 100+ fps, and then the framerate will decide to drop to ~20fps and remain there until I disable Nvidia Reflex in-game.

For Apex, this only happens when I alt+tab back into the game while loading into a match (character select / champion screen). Even then, it seems inconsistent to reproduce -- so that isn't too much of an issue, as the few times it does happen, I can just quickly disable and re-enable reflex to fix it.

However with Overwatch, it usually happens multiple times per match, to where I have to disable reflex to play the game comfortably. I have noticed it pretty consistently happens whenever an enemy Sombra uses their ultimate. It is oddly inconsistent -- some matches it never happens, most matches it happens 3-5 times per game. It also usually happens the first time I load into a match. I tried moving the game off of my HDD and reinstalling on my SSD in case this was due to stutters from accessing the shader/DXVK cache, but that did not make a difference.

I saw that one of the dev branch build artifacts had a commit titled "Reduce jitter strength and pace down factor," which sounds like it could fix the issue (?), but the dev branch build artifacts are expired, so I am unable to download and test that.

Are there any other reports of this happening? If the issue can't be reproduced, let me know which logs/additional info (if any) are needed. Thanks for the amazing work by the way, it at least makes a massive difference in Apex.

The titled is true but towards the end of this post it won't be lol because I encounter a weird bug I think its specific to having the installed game on a different drive. for example on my setup before I fixed the problem by redoing the steps but having apex on the same drive.

here is how it was structured

drive: a) has apex on my mainos drive: b) accessing apex in drive a where originally I was using drive:a as my gaming but decided later to use a new os for my gaming. After finishing the new install and downloading the required packages to get steam to run apex. A biit later, I got everything all setup an running, now I just imported my steam library where in this case would be in drive:a so I choose drive:A/home/kunihiro/.local/share/Steam... and it found my apex install thats good.

Drive:A ) Main OS/
├─ Apex - installed with MainOs steam install 
Drive:B ) Gaming OS/
├─ Steam accessing Apex in Drive:A

at this point I grabbed lutris fixed up everything there along with the env vars for apex to get latencyflex running. I installed everything to the right place but a weird things I had to do was directly set the DXVK_CONFIG_FILE=/fullpathto/dxvk.conf in lutris as directly place the dxvkl.conf in the apex folder will result in a error outputted in the logs using the env var in launch options for apex PROTON_LOG=1 DXVK_NVAPI_LOG_LEVEL=info

so to solve this I had to redo every step slowly and moving my Apex to my GamingOs and setting the dxvk conf env var.

additional information:

My main os has the folder with the appid on the main os so when I start apex it starts the wine prefix in the main os where I had originally installed apex and not the second os.

so my gaming os does not create the folder steamapps/compatdata/**appid** as it is already using the one created on the main os drive:a/home/..../steamapps/compatdata/**appid**

my logs got overwritten as I keep starting Apex... sorry about that

The documentation says to include DXVK_NVAPI_DRIVER_VERSION=49729 DXVK_NVAPI_ALLOW_OTHER_DRIVERS=1 when enabling latencyflex, but this is unnecessary for people using Nvidia GPUs.

I suggest having a version for Nvidia GPUs and one for everyone else. That way the game will see the actual driver version rather than 497.29, which is out of date.