I added the current save. My first time reporting a bug like this not really familiar with the process.
I did something to try improving the thing:
1. PC restart (solved most of the part)
2. I did clean up the mess laying around, it wasn't that much.
3. I changed most of the priorities keeping dupes with small tasks.
4. I changed and blocked some of the useless paths I don't really care.
5. Stairs with gaps I think are not good since its adding paths instead of calculating only one, not sure but I tried removing gaps anyways.
Now this save is the most recent and everything is now a giant pipe because I was like **** it I don't really need more from now on, I will do a steam rocket since gas vents are not lagging.
The lag was before the whole bottom part even existed (pipes wise).
The game flow was like:
1. I built the oxygen generation from that vent near, then the showers.
2. I discovered the other two steam vents and I added that long pipe to bring all the water in one spot (reservoirs).
3. I built that thing in base for a future farm (not connected with the rest)
4. I started to build the cooling water around that entropy machine and from there it started to lag, then I connected with the farms.
5. I started to clean all the mess and paths etc didn't helped much.
6. Built the bottom part in a very painful way, I just went cooking some food while they did the pipes.
7. I don't even know why I continue this world, its kinda a ****ty generation if you ask me but I am first time close to going into space so I am just gonna push it, colony is very stable.
Also I am not one of the best players, I do things on spot without really looking for tutorials or blueprints so efficiency is not gonna at its best in that save file or even in the future, I like learning by mistakes.
In my opinion gas vents are much more heavier than liquid pipes for the processing power in my save file.
Game still freezes in this save for 1 second or two when a pipe is built, it lags only when the dupe finishing the build/repair, at least is not that bad now since I am building one or two for small changes.
As for specs:
GPU is garbage like straight up.
CPU have enough cores for this, its only the liquid pipe causing lag, in rest is smooth all the time and this is the first time causing heavy lag.
rams don't stay more than 60% I would have understood if it was 90% or something.
And yea is the most recent version and I am not in any branch
If the file is not ok let me know, but I think I got the right last save.
Thank you for your time guys