Today, I tried the Memcache class of falcon, and according this the documentation (https://docs.phalconphp.com/en/3.3/api/Phalcon_Cache_Backend_Memcache),
flush() should invalidate immediately all keys queryKeys() should return a table with all keys.
It doens't work at all.
I us the very last version of phalcon, but no chance. Did you try ?
Thank you all for your advices.