My minecraft is laggy and I got Java and optifine?

Try turning off clouds, view bobbing, detailed trees, turn down particles A LITTLE bit but not too much, and try to close all other windows on your computer WHILE playing. It depends if you want to do those. You may also need to check if the inside of your computer is dusty, or "clean" your desktop by deleting files you don't need to make more elbow room…

My son plays that game all of the time but he doesn't use optifine and his game works fine

Basically everything J said and also turn particles off if possible keep the render distance minimal and it also depends on how much ram you have on your computer. If you have a new pc with 4 gb ram it should would without a problem. If you have a older pc i would suggest if possible upgrade your ram 8 gb should work great. You could buy ram cards from amazon, ebay, or just google it you will find it.

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