CS2 Input Lag Explained - The Monolithic 64 Hz Client Simulation Tick Stalls the Render Thread

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soul4kills
Posts: 102
Joined: 01 Aug 2025, 01:30

Re: CS2 Input Lag Explained - The Monolithic 64 Hz Client Simulation Tick Stalls the Render Thread

Post by soul4kills » Yesterday, 14:41

15.625 is exactly windows 11 default timer resolution. Windows 11 has a dynamic timer resolution where each app will wake up to do work at an independent interval. What you might be seeing is background processes waking up every 15.625ms to do work, and that is what's causing that issue.

Enable "GlobalTimerResolutionRequest" in your registry. And see if that interval changes.

unconnected
Posts: 62
Joined: 08 Oct 2023, 19:52

Re: CS2 Input Lag Explained - The Monolithic 64 Hz Client Simulation Tick Stalls the Render Thread

Post by unconnected » Yesterday, 19:57

soul4kills wrote: ↑
Yesterday, 14:41
15.625 is exactly windows 11 default timer resolution. Windows 11 has a dynamic timer resolution where each app will wake up to do work at an independent interval. What you might be seeing is background processes waking up every 15.625ms to do work, and that is what's causing that issue.

Enable "GlobalTimerResolutionRequest" in your registry. And see if that interval changes.
Thanks for the input, I've tried with global timer resolution request on and it's even more clear now.
Image
Btw gpu wait spikes proves that the engine locks render pipeline when processing a tick

soul4kills
Posts: 102
Joined: 01 Aug 2025, 01:30

Re: CS2 Input Lag Explained - The Monolithic 64 Hz Client Simulation Tick Stalls the Render Thread

Post by soul4kills » Yesterday, 21:06

Looks like your gpu stabilized. GPU busy is when your gpu is drawing out the scene. Doesn't look as erratic as your previous screenshot. It's also running at under 1ms. Before it was running above 1ms.

cuaderno
Posts: 20
Joined: 02 Feb 2025, 20:26

Re: CS2 Input Lag Explained - The Monolithic 64 Hz Client Simulation Tick Stalls the Render Thread

Post by cuaderno » Today, 03:58

Assuming this is correct, what should players do regarding settings to minimize the impact? fps_max 400, fps_max 0, gysnc+vsync?

A consideration when testing is that cs2 frame cap works differently depending on wheter you use a number too low or if you are running an offline server.

Moontrance
Posts: 8
Joined: 27 Feb 2025, 07:41

Re: CS2 Input Lag Explained - The Monolithic 64 Hz Client Simulation Tick Stalls the Render Thread

Post by Moontrance » Today, 11:46

unconnected wrote: ↑
Yesterday, 19:57
Thanks for the input, I've tried with global timer resolution request on and it's even more clear now.
Fps max question is valid, seems like you didn't use any limiter cuz normal frame time is around 1ms. Can you redo your test with fps_max 320? Assuming spike is around 3ms, you should have stable 333fps on average. But my guess those spikes just will be higher, cuz limiter is kinda broken in this game. Probably worth another test with external limiters like nvcp or rtss, reflex on/off, etc.

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