What is SQL Server hybrid buffer pool and persistent memory optimization?

Hybrid buffer pool allows direct access to persistent memory (PMEM) to reduce IO latency.

Hybrid Buffer Pool (HBP) enables SQL Server to treat persistent memory (such as Intel Optane or NVMe-backed DIMMs) as an extension of memory. Instead of copying pages between disk and buffer pool, SQL Server can access persisted pages directly in-place. This reduces IO latency and improves restart recovery time. It changes the traditional buffer pool architecture by blurring the line between memory and storage.