@jtcbrown This type of stutter is sometimes caused by other mods like bandits, maps, or texture errors that keep writing to the file.
If you check the console file, you'll find the answer.
I use it on a hardcore server with 500+ mods with no problems.

This legitimately cut the CPU usage in half and made the stuttering bearable

This fixed the insane suttering problem I had, even after playing multiple hours on insane density, very strange to me that the resourse monitor didnt show me any incresead cpu,ram or gpu usage so I am even more happy. Thanks a again bud

Not blaming this mod, I use a lot, but this is not fixing the stuttering for me.

For me, it seems like if I move from one "cell" to another, the lag starts and then will not go back to normal even if I get to a zero zed pop area like my base (though the lag lessens in such cases, still happens.)

Currently going through my mod list again to see what the culprit may be.

I confirm that, bro fixed the in-game server after I wrote to him on Discord, he's cool, so join his server if u want to play with someone ;D

@xxx_420_Bad_Boy [Wizard_Cum] thanks bro, correction done :)

@SimpleKing329 thanks i've moved this line out of the code :)

New version added, now it's possible to host a server with b41.78.16

@ lol, what? yes you need to download the server fix from yt

@Qwzmda Yes, you did everything correctly, if you want I'll try to help you

Works great, thanks!

Hi, i have a question about server fix. What you uploaded to mediafire doesn't work, and there's no response in the comments on YouTube or steam either. You've been told this at least 3-4 times, but you ignore it.) I download b41fix and drop it into the root folder, after which the server does not work. Next, we download serverfix and drop it into the same root folder of the game. The server is still down.) Judging by your answers, everything is done correctly everywhere. What could be the problem? if it's about a local server. For two people

Running B42 and getting the frequent lag & stuttering others have noted.
Tried all the suggested fixes (frame rate, texture compression, borderless windowed, etc. etc.) but none of them stopped the problem.
Tried these modified files and so far, all the areas I was getting lagged out (typically areas with a modest zed population), have little more than an occasional stutter.
Worked for me, I'd definitely recommend this fix.

Guys if your game dont start make sure while copying to not include ProjectZomboid64.json, ProjectZomboid64.bat in the text you are copying.
Look for my comment in the pinned discussion "B42 Installation Instruction (Windows OS)"
I cant put the full comment here (1000 characters length max).

Hi, thanks for your work!)
Can you tell me if the mod only works on a dedicated server? If not, how can I install it on a server that runs inside the game?

it never wants to use more than 8g of ram. i have the edited files and the mod enabled in the modlist. i also have 32 gigs of ram. also how come the mod deactivates steam overlay?

ProjectZomboid64.JSON
del:
"-Djogl.disable.openglcore=false",
"-XX:+OptimizeStringConcat"
B42.12.3 OK

If I have figured it out correctly, you should change the instructions from

" Fixed version of ProjectZomboid64.json and ProjectZomboid64.bat build 42.11.0, 42.12.0 and 42.12.1 (see ready-to-copy files also on
Ensure that both files stored on
"C:\Program Files (x86)\Steam\steamapps\common\ProjectZomboid" (use any text editor)"

to

"Replace the contents of ProjectZomboid64.json and ProjectZomboid64.bat in C:\Program Files (x86)Steam\steamapps\common\ProjectZomboid with the following text in any text editor and hit save. The mod must also be activated in-game."

The installation instructions are gibberish. Could you please rewrite them?

@Jason_Snow i play start button on steam and works fine

@victor nope you have to convert the .bat file in .sh file

@Яйцеслав Зиготос we are using this mod in a server withj 50+ players and +500 mods...check all the files and replace it with the server fix

Only works if I launch by executing the .bat file. Maybe this is how it is supposed to work but I didn't see any instructions to do this anywhere. Using steam to launch the game fails to do anything.

work fine on my WIndows PC, doesn't work on my Linux laptop :/

any fixes for Linux users?

@4Zeta Yes, i use that fix at Project Zomboid Dedicated Server, but I cant launch. After setup the files i cant launch Project Zomboid Dedicated Server. I dont know why, maybe i have win 11?

@Яйцеслав Зиготос you need to use the server fix (youtube link))

Guys, help me please, what I should do if mod working, but I cant launch the server?

Do I need to enable this mod every time I start the game? I saved it to my mods list and for my save, but when I restart the game it turns itself off

Yes? its a big question? how to set it up for Mac OS to use on M4 processor))

Does this also work for macOS?

Guys, please help me, how do I edit the .bat file in Linux? I can open the .json file, but the file that would be the .bat in Linux doesn't have an extension and when I open it as text, it appears with an encoding that I don't recognize. Does anyone know how to help?

not both of them, just the JSON files made the game won't launch

My game cannot launch after i put those 2 files into project zomboid files, pls help

This makes a huge difference. I'm barely noticing any stuttering when driving fast down neighborhoods. And that's with over 250 mods installed.

@4Zeta
I don't know anything about optimization but some games give you launch options so maybe they could do that so people with high end PCs can have their expensive hardware used by the game.
Anyways, thank you for this, my game is much smoother now. Cheers.

does this help with the huge stutters occuring and staying when you drive past filled buildings too fast?

@AndrewMV thanks ;)
but the original setup of the game is for all type of Pc build and you can run it basically everywhere , this mod with old pc isnt effective

You should work for Indie Stone so they finally have someone that knows how to make their game run decently.

@4Zeta ah i see, thanks for the information

@paper Dev choice i guess, maybe they have to rewrite a lot of code with the new vers, if you check with b41 there isnt a guava lib. it's a b42 implementation

Just wanna ask why guava-23.0 instead of newer versions like guava-33.5.0 is used. Would using the latest guava work? If it works then is it better or worse?

b41 or?

@B.I.G. the maximum defined by this config is currently SET MEM_MAX=10240m.

In simple terms, the script checks how much RAM your device has. If it’s more than 16 GB, it launches the JVM (the Java "engine" used by the game) with a maximum heap of 10 GB (MEM_MAX). If you have less RAM, the script automatically uses smaller values to match your specs.

10240m is just the syntax for 10240 MB, which equals 10 GB. You can ask GPT or search the Java arguments -Xms / -Xmx if you want to experiment. For example, -Xmx48g would set a 48 GB max RAM (heap).

Keep in mind the game may use more RAM overall because it also has the graphical interface and native allocations in addition to the internal Java “server” part. However, giving the game a much larger heap than it needs won’t improve performance - it tends to delay garbage collection (cache cleanup) without real benefit, and may even have opposite effect to performance.

@ivmakkk I have 64gb of memory, and it uses a maximum of 21.7 with this mod. What is the limit in your files?

Hey @B.I.G. , my version is fully based on the original mod config, just added small compatibility tweaks for B42.11+ based on comments posted here months ago. So no extra optimization beyond what the mod already offered - just making it work :)

RE more RAM: I don’t think there’s much benefit in using more than 10–12GB. You can try manually setting `SET MEM_MAX=10240m` to a higher value if you see in the OS performance monitor that the game uses all RAM defined in the config, but it’s unlikely the game will utilize it effectively or give any extra FPS.

@B.i.g the mod is workin is the same of Ivmakk now :)

@4Zeta Hi! Are your changes very different from these files?
https://gist.github.com/ivmakk/b6026a539c620e5580e32f1179fe12a2

@ivmakk Привет! Я изменил файлы, как ты сказал, и всё работает. Спасибо! Оригинальный мод теперь более оптимизирован, или твои файлы лучше? А что, если у меня 64 ГБ памяти, а я хочу выделить ещё больше?

MOD UPDATED!

I don't know if this mod will be updated but as for now (42.12.0) the modification prevent the game from launching