Hybrid buffer pool for SQL 2019 vs in-memory

Hi,

I have read the hybrid buffer pool for SQL2019 and from my understanding, we can put the MDF and LDF file inside PEM (which will be seen as a hard drive from OS perspective) and acheive better performance since PEMS will work as a secondary cache and we can avoid Disk I/O. My question is how does it work in context of in-memory OLTP database on SQL2019?. Even for in-memory DB, the complete table(s) will be in buffer pool correct? . if yes, how does this new feature perform better when we have In-memory OLTP? Appreciate all your answers.