Cache is not properly cleared

Hi there,

according to the plugin statistics, its size on my website is currently 590 kB. But according to INFO in redis-cli, the server consumes more than 40 MiB:

# Memory
used_memory:27368456
used_memory_human:26.10M
used_memory_rss:41922560
used_memory_rss_human:39.98M
used_memory_peak:44870648
used_memory_peak_human:42.79M
used_memory_peak_perc:60.99%
used_memory_overhead:3045208
used_memory_startup:809696
used_memory_dataset:24323248
used_memory_dataset_perc:91.58%

Also, there are currently over 40.000 entries in the cache, which I doubt is all needed, since the website is not that large. This value always rises unless I restart the Redis server. However, I would expect that the plugin invalidates and deletes orphaned cache entries by itself. But that doesn’t seem to be the case.

Best regards,
Matthias