Ceph: Changing parameter "mon_memory_target" does not work at runtime.

Issue

Changing parameter "mon_memory_target" does not work at runtime.

mon_memory_target:

# ceph config help mon_memory_target
mon_memory_target - The amount of bytes pertaining to osd monitor caches and kv cache to be kept mapped in memory with cache auto-tuning enabled
  (size, basic)
  Default: 2147483648
  Can update at runtime: true   ## Does not work
  Services: [mon]