A cache tier has several configuration options that define the cache tier policy. This cache tier policy is required to flush data from the cache tier to the storage tier in case of a writeback
. In the case of the read-only cache tier, it moves the data from the storage tier to the cache tier. In this recipe, I have tried to demonstrate the cache tier with the writeback
mode. These are some settings that you should configure for your production environment, with different values based on your requirements:
For production deployment, you should use the 'bloom filters' data structure:
# ceph osd pool set cache-pool hit_set_type bloom
hit_set_count
defines how much time in seconds each hit set should cover, andhit_set_period
defines how many such hit sets are to be persisted:# ceph osd pool set cache-pool hit_set_count 1 # ceph osd pool set cache-pool hit_set_period 300
target_max_bytes
is the maximum number of bytes after the cache-tiering agent starts...