Packet-loss-like lag, network-unrelated

[ayles]

I recently tried playing on linux and noticed an interesting lag. It feels just like when packets are lost, except it seems to be something else.

Some facts:

• It is fine on windows on the same machine (dual boot) - same settings, network.
• It is not graphics-related problem - FPS is consistent, no spikes/drops.
• It IS networking problem in a way - only reproducible when watching live game or when playing, and is not reproducible when watching replay, watching live with delay (there are some sudden lags, but way less noticeable) or playing local demo.
• There are no packet losses reported by the client, also ping is small and consistent (27-40ms depending on a server/whatnot, mostly stays constent for the whole match).
• It is more noticeable after 10-20 mins into the match (tried switching different live games). I guess this lag depends on the amount of entities/events in the game.
• In the late stage of the match, lags appear every 10 second or so.
• I can increase rate to 1-2 seconds with binding game to 1 CPU core (tried experimenting with clocksource and E-cores).
• Changing clocksource to hpet or binding game to one particular CPU core taskset -apc 0 $(pidof dota2) does not help, only reduces FPS, as expected.
• It is reliably reproducible on my machine.

It kinda looks like the client's timer is suddenly being adjusted, resulting in a big delta time for the next frame. Also, if directional camera movement is client-side, there is no way it is affected in the same way as entitiy positions/animations, right?

https://github.com/user-attachments/assets/978d6b0d-2cd2-4c86-8cea-b043c88e3c1d

[TheSiriuss]

I do have exactly same issue with my dota client on void-linux. Did you find the solution?

[ayles]

I do have exactly same issue with my dota client on void-linux. Did you find the solution?

Nope(