Game stuck on ping > 300ms

[illwieckz]

I reproduce it on “Rakka Takka” server which is located in Australia.

When the ping is larger than 200ms, the game is stuck. I believe it's a bug, the game should lag a lot, but not be stuck.

[illwieckz]

I have common.framerate.max set to 0 meaning I get high framerate around 300 fps, but still under the 333 cap (that is enabled anyway).

If I reset common.framerate.max, I get capped at 125fps as expected, the game unstuck itself and I can move around freely but then the game wrongly displays a ping of 999ms which is not true.

[illwieckz]

When I'm stuck, the game continue to render things (I see bots playing), but the input are dead.

[illwieckz]

I still get the bug if I join with a 0.54.0 client.

[illwieckz]

It looks like the bug occurs if ping (ms) + fps is high, to reproduce the bug one should have both high fps and high ping.

The higher the ping is, the easier you get the bug with lower fps. The 333 fps cap is not enough to avoid being stuck if you have 300 ms ping, for example.

[illwieckz]

What is stuck is the input, the game renders properly and updates according to server state on every frame, we can see bots moving around and beacons moving on screen.

[illwieckz]

The bug was already there in 0.54.0, I guess I only noticed it after 0.54.1 was released because we improved performance.

[illwieckz]

I reproduce locally if I spawn a server listening on localhost and join with a client, and emulating a 600fps ping on lo interface:

sudo tc qdisc add dev lo root netem delay 300ms

With 600ms ping, even 125fps is already too much and inputs stop working.

Edit: Setting 300ms in fact gives 600ms.

Edit: To remove the emulated ping, one does:

sudo tc qdisc del dev lo root netem delay 300ms

[illwieckz]

Well, the command likely gives a 600ms ping since both server and client gets 300ms ping, that just makes the bug more obvious.

[illwieckz]

I reproduce the bug with 170fps and 300ms ping. So it means our default 125fps maximum framerate is what prevents European people to get the game being stuck when joining the Australian server.

[illwieckz]

When the bug occurs, the game displays 999ms ping, even if it's 300ms (netem delay 150ms).

framerate	network ping	displayed ping	game experience
60fps	300ms	300ms	playable
125fps	300ms	999ms	playable
170fps	300ms	999ms	stuck

[illwieckz]

The scoreboard displays the real ping (300ms in my example).