Stratozzz

So here is my problem, I've already searched the forum for any solutions, but couldn't find any. I'm currently playing Minecraft 1.12.2 with Forge 14.23.5.2854, Optifine_1.12.2_HD_U_F5, Dokucraft resource pack and a bunch of mods that don't generate incompatibility. Everything starts fine, all mods boot up correctly BUT, if I touch any option from Optifine in-game, FPS drop down to 5-18 and PC slows every process, it becomes a snail in other words. When I open Task Manager I can see that Java ONLY process is using 5 Gb of HDD (idk how that is possible?), showing HDD is at 100% of usage and almost 3 Gb of RAM. I've disabled a bunch of Windows services and other options, now my PC starts up faster and runs faster than before, but MC still does the same thing. Is there anything I can do to stop that? What can I do with Java? I own Java Version 8 Update 261 and my PC specs are these: - Windows 10 Pro, 64 bits. - 8 Gb RAM - Intel i5-8300H 2.4 - 3.8 Ghz. - NVIDIA GTX 1050 4Gb. I hope someone can help me on this one. Thanks.