It can actually be useful for security - you can tell the DPUs to erase memory the moment the OS frees it, reducing the risk of data being read or decrypted. That's probably a very trivial use of the tech, but it's a low hanging fruit.
I suppose one could put more of an OS's work with memory into this level, too. Zero it when it's freed, but also keep the free block list updated at this level. Maybe use these processors for aggregating available contiguous blocks when necessary, too. Maybe use these processors to update the virtual to physical mappings and keep free space optimized. Then, when the application actually needs to do something close to RAM it could be given access.
