I can add RAM ans is there a way to increase rocksdb caching , can I increase bluestore_cache_size_hdd to higher value to cache rocksdb?
In recent releases it's governed by the osd_memory_target parameter. In previous releases it's bluestore_cache_size_hdd. Check release notes to know for sure.
This we have planned to add some SSDs and how many OSD's rocks db we can add per SSDs and i guess if one SSD is down then all related OSDs has to be re-installed.
Yes. At least you'd better not put all 24 block.db's on a single SSD :) 4-8 HDDs per an SSD is usually fine. Also check db_used_bytes in `ceph daemon osd.0 perf dump` (replace 0 with actual OSD numbers) to figure out how much space your DBs use. If it's below 30gb you're lucky because in that case DBs will fit on 30GB SSD partitions. https://yourcmc.ru/wiki/Ceph_performance#About_block.db_sizing
-- Vitaliy Filippov _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
