All of our servers are deployed with Aikars Optimized JVM arguments, which can be found here. These flags will help you run your server consistently without any large Garbage Collection spikes. You'll see better and more reliable stable TPS.
java -Xms12000M -Xmx12000M -XX:+UseG1GC -XX:+ParallelRefProcEnabled -XX:+UnlockExperimentalVMOptions -XX:+DisableExplicitGC -XX:-OmitStackTraceInFastThrow -XX:+AlwaysPreTouch -XX:MaxGCPauseMillis=100 -XX:G1NewSizePercent=30 -XX:G1MaxNewSizePercent=40 -XX:G1HeapRegionSize=8M -XX:G1ReservePercent=20 -XX:G1HeapWastePercent=5 -XX:G1MixedGCCountTarget=8 -XX:InitiatingHeapOccupancyPercent=15 -XX:G1MixedGCLiveThresholdPercent=90 -XX:G1RSetUpdatingPauseTimePercent=5 -XX:SurvivorRatio=32 -XX:MaxTenuringThreshold=1 -Dusing.aikars.flags=true -Daikars.new.flags=true -jar server.jar
Because of these JVM Arguments, your RAM usage might seem higher than normal. It will probably look like it's maxed out, like below.
This doesn't actually mean that you are out of RAM, so this isn't a problem. These arguments will make your server run better. The current RAM usage on the Panel isn't as accurate as the real RAM usage. For this, you can use commands like
/gc to check your actual RAM usage in game.
On the Raw Power Panel, you will see a subsection called "Startup Settings." Since our newest panel update, you are able to add your own custom flags! However, be certain that the flags you add will work, otherwise your server will not start. Only use this feature if you want to edit or alter the already deployed by default Aikars Flags.