[A18] [0.18.1719] Heavy lag at regular intervals

[qdeqde]

I have a colony around 3 ingame years old on tropical forest:
- no mods
- custom work priorities
- walled off base with funnels as killzones with fall traps.
- Around 40 colonists, is this considered late game ?
- around 100 animals , half of them hauler pigs other muffalos and alpacas
- a third of colonists on night shift ,sleeping from 11h to 18h

Started as a new game after getting A18 beta
Getting regular heavy lag slowing down to 3-4 fps at 3x speed, normal fps is 14-18fps at 3x speed
Regularly at every ingame 6 hours:
0h , 6h , 12h, 18h
The lag happens even at normal speed 1x
It started slowly getting longer and longer and now it takes 5-10 seconds until the lag is gone.

What could be the problem?

Happened also with previous version 0.18.1717

I uploaded a video https://www.youtube.com/watch?v=YR-k2CXmPjs

Save file https://www.dropbox.com/s/14ber7i97e99mrx/Solidarity%27s%20Clifft%204t6%202342.rws?dl=0
Log https://www.dropbox.com/s/6rsqne8jsjqo82d/output_log.txt?dl=0

Thanks.

My PC:
cpu i7 6700k
ram 32GB
gpu AMD R9 390
ssd SAMSUNG 850 256GB

[ison]

Could you please upload a savefile where this is happening? It will help us identify the problem.

[qdeqde]

Added save file and log.

[ison]

Thanks, it looks like it's caused by the WorldPawns garbage collector. I've optimized it (for the next A18 unstable build). It can still take ~20 ms per frame, but at least it won't be as laggy as this.