Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Evans]

Guys,

As a part of my defences in every fort I build, I generally dig a 3 tile wide moat 3 tiles away from map edge around the entire map.

In 0.34 it was no problem, and with creative use of bridges allowed me to capture or kill anything that entered the map from any direction and was not flying.

In 0.43.03 (I am using masterwork) I needed to tune this strategy a bit - I channel a 3 tile wide moat 4 tiles away from the edge and then dig 1 tile to the side to prevent climbers.

Once I am done however (all 4 sides channeled AND dug) I am experiencing fps hit about 60-80% loss and constant (like in every second or two) lag spikes.

I found this topic here:
http://www.bay12forums.com/smf/index.php?topic=157727.0

Visible areas (Channeled surface - Game Breaking!)

~ I do not know why, but if you channel out the entire surface from edge to edge, you'll notice a ABSOLUTE INSANE fps lose. I am talking losing 500+ fps from digging out the surface, down 1 layer. Access to the floor below is there, nothing is 'floating above' – a clean, fresh map and I lose 500+ fps doing this. Want a simple really, really deep 3x3 moat around the map? Good luck. At 30+ depth I went under 50 fps!

~ I am completely uncertain what causes this, and would others can tell me if this happens to them or not too, so we can theorize what the heck is going on!

I am absolutelly clueless about WHY this happenes. There is a wide tract of land around the map, bridges connect all 4 sides, everything is otherwise accesible(moat included), yet game basically breaks into unplayable mess.

Anyone has ANY clue what could cause this? Should I report it as a bug somewhere? It wasn't there in 0.34 because that was my best defense strategy back then.

I guess I will have to try with the walls and floors on them instead -.-"


EDIT:
I tried to repaint all dug areas with tiletypes. Now it is even WORSE.
FPS drop below 30 and game freezes for a second every second.

Aparently messing with surface area near the map edges is now very unwise.

[Witty]

I'd say this is worthy of a fully fledged bug report here.

[Evans]

Hey thanks.

But I don't think I can report a bug to a masterwork DF mod there?

Not sure if I can reproduce it with vanilla DF >.< my times of playing ASCII are over since I killed chaos god in ADOM over a decade ago.

Edit:
I did some additional testing to eliminate other possibilities.
- disabled temperature
- cut all the trees to make sure it's not them spamming me

Finally I backtracked to the savegame before I finished the moat (had just been channeled on the surface, a year earlier).
I enabled fast dwarf and designated digging.

There was a massive lag spike, then it went back to normal after they finished.
I build a single bridge and disabled the fast dwarf.

Here is what I saw:
- each time creatures entered the map there was a lag spike
- once they began moving around the edges short lag spikes and drop in FPS began
- more and more creatures entered the map so I send military to kill them off

The last step I repetead a few times. Each time a new group of creatures entered a game lost few more fps.
More and more lag spikes as my military chased them around.
As my dwarves began to retrieve all the corpses game turned into the mess mentioned above.

There is definitelly something wrong with pathfinding in situation like this. But why?

I will now load the initial savegame, spawn few thousand blocks and wall the map off.


Edit2:
Apparently when I started from initial savegame to reproduce it, I encountered my semi-mini-beast - immortal Weasel Corpse, which they say no dwarf can kill.
"The recruit bashes the weasel corpse in the head with his |||steel war hammer||| but the attack glances away!"

[Witty]

heh yeah, that's another bug.

[Pirate Santa]

It sounds like digging out large pieces of the surface is screwing with pathfinding.

[Elvang]

It sounds like digging out large pieces of the surface is screwing with pathfinding.

That sounds familiar/similar to the pathfinding bugs that were sources of lag in older versions. IIRC, a workaround was retiring the fortress and then reclaiming it, as it'll remap/hide anything not path-able from the surface.

[Evans]

Hello!

I finished testing with building a wall around the map.
As expected, no FPS drop was observed. I drained the river and let the trees grow back to see if this will affect anything, but I am at stable 100 fps limit all the time, save occasional temperature changes/other events. No lag spikes every second.

It is apparently the issue with channeling the surface here.
I intend to make a bug report about this, however:

It sounds like digging out large pieces of the surface is screwing with pathfinding.

That sounds familiar/similar to the pathfinding bugs that were sources of lag in older versions. IIRC, a workaround was retiring the fortress and then reclaiming it, as it'll remap/hide anything not path-able from the surface.

Would you be that kind as to point me to this bug or at least suggest keywords to look for? The last issue with immortal undead weasel turned out to be 6 y old, so I would appreciate some help with necromancy here.

Oh and thank you sir, for suggesting a kosher dwarvish solution to my problem.
Sending a squad of vanguards to dig the trenches and then returning later with proper pioneers seems to be much more legitimate and decent way of preparing defences.

Honestly, wall project for 5x5 embark took around 5000 blocks to finish, for all the walls, floors, bridges and paved roads.
If I wanted to do it without createitem command that would mean mining at least 4000 rock tiles to get 1000 stones, having to transport them and be turned into blocks. Not to mention manually designing wall sections 10 tiles long gets old very soon.

Digging trench and returning later will do, for now.

[Elvang]

It sounds like digging out large pieces of the surface is screwing with pathfinding.

That sounds familiar/similar to the pathfinding bugs that were sources of lag in older versions. IIRC, a workaround was retiring the fortress and then reclaiming it, as it'll remap/hide anything not path-able from the surface.

Would you be that kind as to point me to this bug or at least suggest keywords to look for? The last issue with immortal undead weasel turned out to be 6 y old, so I would appreciate some help with necromancy here.

The forum thread was about pathfinding cache bugs, if I remember right. On mantis, pathfinding bugs fall under the pathfinding category.

[Spectre9000]

I just recently channeled a magma moat out of a volcano around the entire map. I experienced no frame loss. It was a 3 wide moat. I even had vents flowing off the map for excess magma. I'm on 43.05 though, not 43.03. Could be a mod issue as well.

[Fleeting Frames]

Thank you for researching this. Map-surrounding wall is much more reasonable than the fallback idea of map-surrounding cage traps.

And that's interesting, Spectre.

[Fleeting Frames]

*gestures*

Doublepost, because I think I found a 1x1 5-biome embark.

That sounds familiar/similar to the pathfinding bugs that were sources of lag in older versions. IIRC, a workaround was retiring the fortress and then reclaiming it, as it'll remap/hide anything not path-able from the surface.

Question: If you build floors up to map edge in mid-air where the built location has different sheared biome than ground, can animals of belonging to the biome enter the map on top of said construction? (In my case, freshwater swamp.)

Or is this not possible vanilla due game loading a map larger than visible area?

[PatrikLundell]

My gut feeling is that your building would get only the flying creatures of that biome, and those would appear regardless of your building. You could make farm plots up there to grow freshwater swamp plants, though.

[Evans]

Not sure about the above, but I know they enter on top of build walls in cavers.

As for the issue that started this thread:
Digging a moat and abandoning the fort was a success. It worked well FPS wise, no lag spikes after reclaiming site.

[Fleeting Frames]

Okay, I took a bit to test this. Built a wall, ramp and then hanging floor to map edge, abandoned.

Then reclaimed, used liquids plugin to make it only entrance and made heavy use of region-pops boost-all and exterminate GIANT / exterminate BIRD.



Looks like a success. Water Buffalos are wetland-only creatures. Watched one run right down the catwalk. 

I'd guess that this wouldn't work without abandoning/reclaiming though, since air tiles aren't valid for wagons to enter the map from iirc.

[PatrikLundell]

Interesting results indeed.
A further question, though, is how you find out that you have biome shearing at all? The only cases I've know about it were evil rain that never reached the ground and a farm plot directly above another one (the lower at ground level, the higher on a floor) where the upper plot didn't support any crops.