Some players have reported lag in Factorio for years. Lag always seemed fair to me given the sprawling, complex bases you can build in the game, but the latest patch might make things better. Version 1.1.46, released this Saturday, makes several changes which should reduce multiplayer latency.
There are a bunch of bug fixes in the full changelog, but the latency tweaks are the big ones:
- Reduced multiplayer latency on very good connections by up to 66ms(4 ticks).
- Changed multiplayer latency calculation to be smoother. This should reduce multiplayer stutter on bad connections.
- Changed default network send rate from 30 to 60 packets per second and added an option to configure the rate in server-settings.json.
The top one is the most interesting. The patch notes link to this post on the Factorio forums from 2019. A player spotted that latency was unusually high even on exceptionally good connections; even, in fact, when two instances of the game were running on the same computer.
At the time, Factorio's developers said that, "[latency] could be lowered a bit, and we could probably provide an option to send packets every tick, but solving this isn't a big priority now, as we have the latency hiding and other problems.
"One day, we might try to look at that."
Well, now they have. A developer updated the thread in October to say that, "The issue is quite fundamental to how the game synchronizes it's game updates, network updates and how things are buffered. Hornwitser took a look at at the many issues causing unnecessary delays. In Version 1.1.43 you should see latencies as low as 2 ticks (33ms) on LAN."
So if you've been struggling for years to play Factorio with a pal, even when you've both got mega connections, give it another go now. It might work.
Aside from continuing to update the base game, Factorio's developers are apparently also at work on a major expansion.