Based on that message, it would appear you still have
an inode limit
in place ("mds_cache_size"). Please unset that config option. Your
mds_cache_memory_limit is apparently ~19GB.
No, I do not have an inode limit set. Only the memory limit.
There is another limit mds_max_caps_per_client
(default 1M) which the
client is hitting. That's why the MDS is recalling caps from the
client and not because any cache memory limit is hit. It is not
recommend you increase this.
Okay, this this setting isn't documented either
and I did not change it,
but it's also quite clear that it isn't working. My MDS hasn't crashed
yet (without the recall settings it would have), but ceph fs status is
reporting 14M inodes at this point and the number is slowly going up.