Memory leak

[NastyFlytrap]

Was this bug reported before?

• No, it was not.

Please provide a link to your crash report or latest.log, if relevant

No response

If you have any, please provide a list of additional mods

No response

Please describe the issue you are experiencing

debug.log
latest.log
I am looking at debug.log because my game is stuttering really badly and its using 8.8GB's of memory, plus my pagefile on my ssd, and it says that the world may have leaked like 45 times before i shut the game down due to me being sick of this.

[xJon]

Hey! On the other thread you mentioned using the high-resolution Sphax resource pack, which partially explains the high memory usage. That being said, stutter should not be a part of it. Have you by chance enabled the minimap mob rader? As that is known to cause stutter.
Also, you mentioned adding a mod which doesn't look official, if you want flat bedrock I recommend looking at mods from CurseForge which is a trusted source.
Lastly, could you share your GPU? Some are incompatible with the high-resolution Sphax resource pack which might explain some performance issues.

[NastyFlytrap]

Hey! On the other thread you mentioned using the high-resolution Sphax resource pack, which partially explains the high memory usage. That being said, stutter should not be a part of it. Have you by chance enabled the minimap mob rader? As that is known to cause stutter. Also, you mentioned adding a mod which doesn't look official, if you want flat bedrock I recommend looking at mods from CurseForge which is a trusted source. Lastly, could you share your GPU? Some are incompatible with the high-resolution Sphax resource pack which might explain some performance issues.

No, i didnt enable the mob radar, and i believe my stuttering is because my my memory usage is at 95%, windows presumably wont let the game use the remaining 5% memory, so it has to put it onto the pagefile, which even on an SSD is still quite slow to react, thus lagspike because asking the SSD holds up the entire game.

Lowering my ram usage from 16GB's to 6GB's seems to have fixed the problem. I played on my desktop in the past, but now im stuck on my laptop, where memory is shared with the GPU, so i dont actually have 16GB's available anymore, and i forgot i set that in the technic launcher.

The mod came from curseforge, its even in the name. Im not sure if i mentioned that or not.
Its a 3050 laptop

[xJon]

Thank you for sharing the explanations.

Lowering my ram usage from 16GB's to 6GB's seems to have fixed the problem.

Did you mean the RAM allocation in the launcher?

[NastyFlytrap]

Thank you for sharing the explanations.

Lowering my ram usage from 16GB's to 6GB's seems to have fixed the problem.

Did you mean the RAM allocation in the launcher?

Yes, that. Presumably that was the reason for my lag spikes, data getting pushed to the pagefie, however i do think there is a memory leak, as suggested by the logs, and from what i saw, it seemed to have given those messages whenever my game had a lagspike, however memory usage was going up by a few megabytes every few seconds, seemingly without end, and thats still happening

[xJon]

There are mods installed that are supposed to alleviate this issue. Can you report back after a couple hours of gaming with the lower RAM allocation whether the issue persists?

[NastyFlytrap]

There are mods installed that are supposed to alleviate this issue. Can you report back after a couple hours of gaming with the lower RAM allocation whether the issue persists?

I havent really been able to play since i made the post but i did a quick cursory glance, walking about the overworld, im very early into the savefile so i only have a macerator, furnace, two geothermal generators, etc, and the memory usage is climbing slowly and then i hit as much memory usage as windows will presumably allow to be used, maybe it reserves a couple percent for itself, i dont know, there's a lag spike, my ssd usage spikes to around 25%, and when the lagspike is over the game dumps about 200MB's of memory.

Maybe thats from the mods you mentioned. The part i dont get is how is it that i have 16GB's of memory, and no matter how much librewolf and minecraft use(the two applications i have running), its always around 95% memory usage. When i made the post minecraft was using almost 9GB's of memory, with librewolf using about 2.5GB's, i have no idea how, now librewolf is down to about a gigabyte, with minecraft between 5.5 to 6GB's, and im still at 95% memory usage. Windows is fucking with things and i dont like it.

[NastyFlytrap]

There are mods installed that are supposed to alleviate this issue. Can you report back after a couple hours of gaming with the lower RAM allocation whether the issue persists?

Well im back, and it was fine ish since then, and then yesterday i started playing around with mystcraft, today i played around with it more, i have made a few ages, and now the game freezes for three seconds, every second or two, and restarting the game fixes it, until i go into any of my ages, and then it lags permanently even if i save and quit the world and load back in. Only a full game restart makes it okay.

For the last two weeks memory usage was around 5.6-5.8 or so, now when i launch the game it shoots up to 7.7GB's, even though its limited to 6GB's in technic launcher, and then i load into the world, and it hits nearly ten gigabytes of memory usage, freezes for half a minute, plummets back down to 600 megabytes, and then builds its way back up to around 6.3 gigabytes, and while i was writing this, it finished its things, and it normalized around 5GB's.

I'm going to make another age, and see how that goes, this time observing the memory usage in real time.

It turned out to be a packed ice hellscape where the surface wants to kill me, and my memory usage is up to 5.8GB's. I'll go back to the previous lava surface hellscape to see how that affects the game.

Memory usage is up to 6.4GB's, seemingly stable now, although i am not sure if i went to a different age again, it'd go up or not.

Went to a world i made before that, and its still around 6.3GB's or so. No idea whats happening but after some hours of play it just lags and the game as a whole needs to be restarted to fix it, and half an hour ago when i did that, it took 7.7GB's in the main menu, tried loading a world, tried to take almost ten gigabytes, and it crashed.

[xJon]

@NastyFlytrap I have a hypothesis: Have you changed the world type from default when you created your world?

[NastyFlytrap]

@NastyFlytrap I have a hypothesis: Have you changed the world type from default when you created your world?

I um.... I dont remember? Can i check somehow? I know i edited the world with some tool to turn on cheats, because i forgot to do that during world gen, but i kinda doubt i changed anything. Not 100% sure though.

[xJon]

• You could try manually updating modernbetaforge-1.12.2-1.7.0.0.jar in \modpacks\tekkit-smp\mods to this version.
• Can you please share your crash log using a paste tool, such as https://mclo.gs?
• You can try allocating 8 GB, considering you're using a high-resolution resource pack.
• Can you reproduce the memory issues with Mystcraft consistently? 🤔 Might need to track it using a tool such as VisualVM.

[NastyFlytrap]

• You could try manually updating modernbetaforge-1.12.2-1.7.0.0.jar in \modpacks\tekkit-smp\mods to this version.

  • Can you please share your crash log using a paste tool, such as https://mclo.gs?

  • You can try allocating 8 GB, considering you're using a high-resolution resource pack.

  • Can you reproduce the memory issues with Mystcraft consistently? 🤔 Might need to track it using a tool such as VisualVM.

I actually downgraded to sphax + sphax tekkit smp to 64x yesterday, and the problem is less severe now. For now i am at 5GB's of allocation right now because i have 16GB's for the laptop GPU's vram, because it didnt come with any of its own, windows, a few browser tabs, and im already capping out.

I mea, im not sure how specific you want me to be. Yesterday for example i created two ages, one with 9 empty pages and a linking page, the other with 188 empty pages and a linking page, i flew out further than 1km, on a render distance of 32, and the game started stuttering permanently, and the tick rate was jumping between 90ms and 2000ms, even after leaving the age, and only restarting tekkit smp as a whole fixed it.

For now i'll set it back up to 8GB's on the llauncher.

Here's the log from the crash

2025-10-13-1.log

Edit: Why should i upgrade the mod? What outcome are we hoping for? I did it, but just asking. Also, why not the latest version?

Edit2: Two days ago i also downgraded from adoptium 21 to oracle 1.8 to see if that changes anything. There were changes but i cant exactly articulate them. More testing is required with that.

[xJon]

In the log you provided, it does look like the game ran out of memory: Caused by: java.lang.OutOfMemoryError: Java heap space.
It might be that a high resolution resource pack + Mystcraft usage has higher memory requirements than usual? I think that allocating 8 GB is a smart choice.

The mod update—it supposedly has some fixes to world generation if you did select a Modern Beta world type, and not the latest version as that'd require updating its companion mod (Modern Beta Forge Release Plus) as well but you can feel free.

Also, I didn't realise you use a render distance of 32. That is an extreme render distance that might require additional RAM as well. When it started to stutter, did you notice the game is stuck on 100% RAM usage?

[NastyFlytrap]

In the log you provided, it does look like the game ran out of memory: Caused by: java.lang.OutOfMemoryError: Java heap space. It might be that a high resolution resource pack + Mystcraft usage has higher memory requirements than usual? I think that allocating 8 GB is a smart choice.

The mod update—it supposedly has some fixes to world generation if you did select a Modern Beta world type, and not the latest version as that'd require updating its companion mod (Modern Beta Forge Release Plus) as well but you can feel free.

Also, I didn't realise you use a render distance of 32. That is an extreme render distance that might require additional RAM as well. When it started to stutter, did you notice the game is stuck on 100% RAM usage?

I was only using 32 chunks in that specific instance, since it was a flat world with almost nothing in it save for crappy lakes and libraries. Generally i stick with 10. Obviously that'd skyrocket my memory usage, but its fine when i load in, its only after traveling far from spawn it becomes a problem. Memory usage was around 95% or so. I presume just will not let the game use the last 5% for whatever stupid reason windows usually comes up with....

Lets say i want to update both mods to the latest version, how do i know which version is compatible with which other version? I cant seem to be able to tell

[xJon]

@NastyFlytrap Simply update both to the latest available!

If you are able to consistently reproduce the stuttering issue in Mystcraft, maybe you can add this compatible version of spark and run a profiling session while the issue occurs.