For those of you wondering what the Developer Console is, it's a cut down version of that the Developers actually use on their side. For example, JMods have commands to spawn items, walk through walls, and mute/ban, but this is all restricted obviously. We only have a cut down version, only the things JAGeX thinks we should have.
FPS: Frames Per Second. This is how many frames the game is running at per second, the higher the better. 60FPS is the cap in RuneScape I believe.
Cache: Percentage of Total Game Data stored locally on your computer. The higher the better - 100% means the game is totally cached. Need confirmation at to whether this is local cache, or the entire map (every area).
This means basically, instead of having to load everywhere you go to, if it's 100% stored locally it'll load from your computer, making things much faster
In/out: Network usage by RuneScape in bytes/second (upstream and downstream)
Surprisingly, this is VERY minimal.
Memory: Java memory usage in megabytes. Java is usually allocated 64mb/128mb. This can be increased manually, but at the minute it doesn't seem to do much, and seems to be capped around 128mb of maximum usage.
offheap: System memory or graphics card memory usage in megabytes (Depends on graphics mode) Safe/Software uses System Memory, DirectX/OpenGL uses Graphics Card Memory.
What do these mean? Well basically, if your system is using 100MB of RAM and you only have 128MB of RAM - this could be a reason for a slow system.
If you're using 128MB of "Offheap" or Graphics Card Memory, this could also be a deciding factor in your framerate limits.
It also gives you a visual indicator to play with, so you can try changing settings and see how your framerate increases or decreases
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