[HohPum1l]

> It also might be worth pointing out that you now need 16x the page mappings

It doesn't. The article mentions it's only 3 mappings since those bits are colors, not arbitrary combinations of flags.

> I don't know how Java does it's memory management but if it does lots of small mappings (Which I'm guessing it does not) then that could be a concern.

openjdk generally uses large contiguous mappings but it may punch holes in the middle of the heap if it's configured to yield back memory to the OS. But applications that dynamically shrink and expand their heaps are not necessarily those that are concerned about the last quantum of page table overhead.

> And like you mentioned with the TLB

On the other hand it does support huge pages to mitigate costs of TLB entries.