If the cache statistics are requested using the telnet API, the maximum cache size is returned together with the number of insertions and the number of deletions before expiration of the cache entry (live freed aka evictions). The request is to add preferably the actual cache size or alternatively the number of deletions due to expiration of the cache entry.
Currently one can only see that the cache is too small if the number of live freed entries becomes too large. The opposite, the cache is too big, is not visible. This can be advantageous to know in a resource-limited environment.
The suggested alternative is based on the assumption that the actual size equals the total insertions minus the live freed entries minus the expired freed entries.