Factorio Forums

After prolonged play, the headless server starts to eat 100% of CPU (one core) when no one is connected. If someone connects the load drops to usual 20-30% and gets to 100% back when it's idle. Save attached.

Please upload a screenshot of a diagnostic tool showing the CPU time of the factorio process when the issue occurs.

Have had this issue, can't show much more right now but from my server CPU graph I can clearly see the usage rise to 100% when the bandwidth drops to 0% (indicating all players leaving/desyncing/crashing). It then stays like that for around 2 hours before it drops to 0% (server crashes) and stays there until I reload the server. Makes it very difficult to keep a server going for long

Thanks for confirmation. I'll post a screenshot of htop when it happens again, I've restarted it recently. Just some info, I ran it on my VPS (pretty memory restricted one) and then got tired of constant swapping and moved it to my home PC. I have 32 Gb of RAM and i7-2600 so it shouldn't be an issue to run the game with big map reveal. The server uses almost 900 Mb of RAM now.

rkfg wrote:After prolonged play, the headless server starts to eat 100% of CPU (one core) when no one is connected. If someone connects the load drops to usual 20-30% and gets to 100% back when it's idle. Save attached.

On my server I can see such issue too.

Please try if just pausing the game while being connected shows the same problem.

Loewchen wrote:Please try if just pausing the game while being connected shows the same problem.

I've experienced the same issue on a debian server.

If the game is paused while someone is connected the cpu usage is normal (<1% on my box).
Also, the cpu usage seems to be normal when the server is first started and no one has connected. I haven't tested this extensively but the problem only seems to start after someone has disconnected (but not always immediately afterwards).

Additionally if I stop the server while experiencing abnormal cpu usage it seems to take much longer than usual to stop and I see the following error before it does: This particular error might be to do with the factorio-init script. However the abnormal cpu usage happens when launching the server without factorio-init.


The server is invoked with:

Here are some htop screenshots.

For some reason this time around the cpu usage isn't climbing past 50% and keeps hopping randomly between cores.

I'm having the same issue here : 100% usage of 1 core with no players connected, 0,5 % with one player paused (on a save created in 14.1 with only a few hours ingame).

Experiencing similar issues - (only running 0.14.0 right now) - my AWS server constantly hits the CPU usage cap (of 10%) even when no players are online - however the server has been running constantly with no other problems.

Update: did some further testing and my server CPU usage supports randomic's findings.

V. little CPU usage on startup, then 10% CPU usage with one player connected and then jumping to full CPU usage when there are no players.

Attached is my CPU usage graph with some pointers.

EDIT: Also forgot to mention, server shut down behaves abnormally in the same fashion to randomic's situation after I left the server.

If you guys run the server with --no-auto-pause (so that it won't pause the game when the last player leaves), does the CPU usage still go to 100% after the last player leaves?

Interesting idea - I will try it out with a fresh map soon.

I presume the --no-auto-pause is responsible for adding a client called <server>?
Either way, with this option enabled the server stays at a steady normal cpu usage when no clients are connected. Even after connecting/disconnecting multiple times. I can't do an extended test with the option enabled at the moment but hopefully someone else can.

N.B. The above is from a server now running 0.14.2.

Thanks for the report, it is fixed for 0.14.3 now.