Minecraft Forums

I have a modpack that I created on technic that requires 2gigs of ram to run, I have noticed that if you play it for more than 1/2 an hour it starts to have lag spikes.

I opened the F3 screen and watched as the RAM would hit 97% and lag spike, then drop to about 80 and climb back up, but everytime it hit 97% it would lag spike.

I read that you can use this JVM argument for cleanup in both client and server: "-XX:SurvivorRatio=2 -XX:+DisableExplicitGC -d64 -XX:+UseConcMarkSweepGC -XX:+AggressiveOpts"

HOWEVER, I keep finding info that says to add it to the version.json in the modpack.jar file, the problem? I cannot figure out where to put it in there. I tried putting it below the "minecraftArguments" section like this:

"javaArguments": "-XX:SurvivorRatio=2 -XX:+DisableExplicitGC -d64 -XX:+UseConcMarkSweepGC -XX:+AggressiveOpts"

but my modpack will not detect the modpack.jar file and won't try to load.

now I THINK I know where to put that code in the start.sh/batch file(s) for my server version, but I have no clue where to put it in the client version.

Any help is greatly appreciated.

Anyone got a clue what I can do?

Quote from grimallq»

For custom launcher issues, go to the launcher's own forum.

But current technic should allow custom JVM arguments somethwre in launcher settings.

P.S. -d64 argument won't work unless you set 4GB RAM minimum

The server I run has 8 gigs in it and a minimum of 4 is allocated, I did find the area to add custom arguments into the launcher, but I read there's a way to put those arguments directly into the version.json file so no one needs to add them into the launcher, pretty much making the pack auto-execute those java commands, if that makes any sense.