'-XX:SoftRefLRUPolicyMSPerMB=10000' keeps the soft reference to 10 seconds per MB.If you allocated 2GB of RAM to Minecraft, you need to reduce the number here to half of that, which is 1024m for example. '-XX:ReservedCodeCacheSize=2048m' tells Minecraft to reserve 2GB of RAM for storing code that might be used again.Never ever use ALL the RAM or your computer will crash. Always ensure that your system has at least 2GB of RAM leftover. If you have less than 4GB of RAM, DO NOT use this. '-Xmx3G -Xms3G -Xmn768m' tells Minecraft to use 3GB of RAM.
