[ylyn]

The reason for this is that in Windows the DE is part of the system so it knows what to keep in memory.

On Linux the DE and shell and htop is just another program so when the system is under high memory pressure those things also get swapped out and back in when they need to run. Thrashing.

If you run something like memlockd to keep vital binaries from being swapped out I'm sure you will see that behaviour improve.