[ceph-users] ceph cache pool question

I have a question about ceph cache pools as documented on this page: https://docs.ceph.com/docs/nautilus/dev/cache-pool/ Is the cache pool feature still considered a good idea? Reading some of the email archives I find some discussion of how this caching is not recommended anymore, for version=nautilus. Is that correct? What is my use-case? We are using cephfs, and have a large cephfs pool of HDD with some NVMe drives for bluestore WAL and DB. Total storage is 2.1 PB. Replication=3. There is also a separate metadata pool, as required for cephfs. We have a spare storage server with about 14 TB of NVME drives. Would it be worthwhile to setup an NVMe cache pool for the main cephfs pool? Sincerely, Shawn Kwang -- Associate Scientist Center for Gravitation, Cosmology, and Astrophysics University of Wisconsin-Milwaukee office: +1 414 229 4960 kwangs(a)uwm.edu