when i play single player in mod packs like hexxit,attack of the b team and crazycraft i get major lag however when i play multiplayer i do not lag (well u know only the bits of lag or server lag) i cant play single player with this lag any fix?? btw when watch my fps its randomly jumps to 100,200,500,1000,5000, etc <--- if that makes a different.
You might need to allocate more RAM to Minecraft/Java/whatever launcher you're using.
I had a similar problem a while back. When you press F3, look up in the topright for memory usage. If it gets exceedingly close to, or up to the cap, then you need to allocate more memory.
You should also be sure you're using a 64 bit version of Java, assuming your system is 64 bit.
its 95% so thats the problem however one question what should i put the memory on? is there a easy way to find the best for it? or do i have to keep trying till i dont get it anymore?
I had a similar problem a while back. When you press F3, look up in the topright for memory usage. If it gets exceedingly close to, or up to the cap, then you need to allocate more memory.
You should also be sure you're using a 64 bit version of Java, assuming your system is 64 bit.
Poke around in the settings, and if you can't find anything, you should probably look up how to do it manually.