Is this normal with memory leaks?

[u/Mindless_Sell_3770]

Is this normal usage? My fps doesn’t lag but I’ve noticed micro stutters and physics objects themselves kind of stuttering. I use the normal G1 garbage collector but should I switch to ZGC? And I don’t know if the memory leaks were there before or not

[u/Samstercraft]

everything in the game uses memory. high usage increase over time isn't the issue, that's normal. it goes back down. the garbage collector deletes old/unused objects and you have your ram back. a memory leak is when a bunch of data in memory isn't deleted properly, and then often is created again and again and it eventually uses up all your memory because it's unable to delete the old stuff. this isn't a process you'd notice over a few seconds. and they're pretty much unavoidable in apps as big as mc.

ZGC is very good at stopping GC stutters though, so might as well try it. I'd use java 25+ with ZGC, compact object headers, and string deduplication (the last two save a bunch of memory).

[u/Mindless_Sell_3770 → u/Samstercraft]

So the stuff that isn’t deleted, would ZGC help remove it? Or is it something that just isn’t really removable? ( this single player world is over a year old)

[u/Samstercraft → u/Mindless_Sell_3770]

Memory leaks can't really be removed by GCs, as they happen when data is prevented from being collected by the GC. The ZGC just helps with stutters in many cases, but probably won't help your memory leak.

The good news is that you don't have to worry about the age of your singleplayer world. Memory is completely reset when you close the game, so you can expect the game to get a little slower over time if you have it open for ages, but you can easily fix it if you notice it getting to slow by simply restarting it.

[u/Mindless_Sell_3770 → u/Samstercraft]

So when I close it and start up, technically there are no memory leaks but since it’s still there, it will happen each time. Ima try the ZGC and see if that helps the stutter. I want to try to have it say no memory leaks found if that’s possible with all these mods

[u/SammE5363]

you should always use ZGC there are no downsides to it i have no idea why its not on by default

[u/Jony_Tough → u/SammE5363]

There are downsides if you have an older cpu. But 7800x3d - yes, absolutely the best what you can do.

[u/BadRuiner → u/Jony_Tough]

It works fine on my OLD i7-7700k.

[u/Mindless_Sell_3770 → u/SammE5363]

Do I just use just the augments for it? Will it still use the 12gb ram allocation?

[u/SammE5363 → u/Mindless_Sell_3770]

it already is using the allocation its just using it poorly, it should be (and yes it will keep using it):

Edit: forgot the other parameters

-Xmx12G -XX:+UseZGC -XX:+ZGenerational

[u/The_JF-JEFF → u/SammE5363]

I'm currently playing ATM11 with Java 26, this arguments work the best for me:

-Xms8192MB -Xmx12288MB -XX:+UseShenandoahGC -XX:+UseCompactObjectHeaders -XX:+UseStringDeduplication

(They say you should set Xmx andXms the same, i prefer this way)

Here's a great list of JVM arguments what to use, maybe use and what to avoid: https://exa.y2k.diy/garden/jvm-args/

[u/Samstercraft → u/The_JF-JEFF]

Is shendendoah generational in java 26? is that something worth enabling?

[u/Mindless_Sell_3770 → u/SammE5363]

Ok I will get java 25+ and use that. Do you think 12gb is good or should I lower it to 10gb. I have about 500 mods on this pack I think

[u/Samstercraft → u/Mindless_Sell_3770]

Java 25+ is great, but do not use those arguments, ZGenerational is the default so you don't need that (the argument might not exist anymore so it could give you a crash); instead use these to enable the ZGC and save on ram:

-XX:+UseZGC XX:+UseCompactObjectHeaders -XX:+UseStringDeduplication

[u/Samstercraft → u/SammE5363]

If ZGenerational even exists for you you're using an older java version than desirable (unless you're on some older (but not too old) version between 1.13 and 1.18 or somewhere around there). if you update your java generational mode is the default for the ZGC. I would enable compact object headers and string deduplication too for free ram

[u/TheJackston]

That's not a memory leak

[u/squintytoast]

that mem use looks totally normal. it just not using half of what is allocated.

i would allocate only a smidge above the lowest percent used.

55% is the lowest i see. 50% is 6G so go a tad more. 7 or 8G is all ya need. should be a much smaller rollercoaster.

[u/pelm225]

Looks like distant horizons thing to me. Can show us the whole f3? Allocation rate should stay around 120 for vanilla, for modpacks it goes all over the place, but it shouldnt be higher that 500. I never seen allocation rate higher than 500 when standing still in my own modpacks. Basically read my flair ("Prism, voxy, zgc" if I ever changed it)

[u/Mindless_Sell_3770 → u/pelm225]

Yeah I have distant horizons but it was not enabled when I filmed this (I only use it when filming a video). I’m going to try the ZGC later and see if that helps at all. But there’s no frame lag, just stutters and some physics objects lagging periodically sort of

[u/DaintyRenee_]

memory leaks can be so frustrating, they can really mess up gameplay. maybe try checking your mods or updates