[Rseding91] [0.13.15] Headless Server Desyncs

[edalquist]

We are running a headless server with no mods on Google Cloudand generally it works great but every once in a while we get repeated desyncs.

Attached is a zip with 3x desync reports
- It was just me on the server
- I generally have a <15ms ping to the server
- factorio is the only thing running on a single core server with 3.75GB of RAM, our factorio process generally uses just under 1GB.
- Server: Linux factorio-server 4.4.0-31-generic #50-Ubuntu SMP Wed Jul 13 00:07:12 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
- Client: OSX 10.11.6

https://drive.google.com/open?id=0B0KQR ... 0ZOdVl2NjA

[Loewchen]

Are you using mods?

[edalquist]

No mods (I did say that in the original post).

It appears to be save related. We have the server set to autosave every 5 minutes and have 24 slots. I slowly went back in time until I found a save that worked.

Here is a drive folder of the saves: https://drive.google.com/open?id=0B0KQR ... C1vdTF5TVU

save 20 works saves 21-24 result in immediate desync.

We restarted from save 20 and played several more hours (yay factorio) without problem.

[Rseding91]

Thanks for the saves. I was able to reproduce the desync. I'm looking into it and will report back when I've figured out what's going wrong.

[edalquist]

Awesome, glad to give you usable data. I realized that after I verified save 20 worked I never went and re-verified that save 24 caused the desync still and it wasn't some transient issue.

[Rseding91]

Fixed for 0.13.16.

[edalquist]

Awesome thanks! For a curious software engineer can you share what the bug was?

[Rseding91]

Fast replacing a filter inserter with the condition "set filter" with an inserter that doesn't have filters.

[Kurtosis]

Yay! So glad we got it fixed! This isn't the first time we've hit this bug either )