Also : configuring correctly APCu seems to have definitely sealed the deal. I only had “apc.enabled 1” in my APCu config file, so I found all the other stuff to add here : PHP: Configuration à l'exécution - Manual
Now my 20-apcu.ini looks like this :
extension=apcu.so
apc.enable_cli=1
apc.shm_segments=1 # default = 1
apc.shm_size=128 # default = 30
apc.ttl=7200 # default = 0
apc.user_ttl=7200 # default = 0
apc.num_files_hint=1024 # default = 1000
#apc.mmap_file_mask=/tmp/apc.XXXXXX # default = no value
apc.enable_cli=1 # default = 0
F*ck me, configuring this correctly is tough. Hopefully it will hold. Thanks a lot again !!
Edit : this also helped greatly with my CalDAV tasks’ speed, it was horrendous aswell Several issues after upgrading to Nextcloud 21 - #2 by newhinton