As I understand it, if I increase the CacheSize value and run zabbix_server -R config_cache_reload, the Zabbix server will understand this and will increase it. This is also done at the time set in CacheUpdateFrequncy. Are these two statements right? Because I can be wrong.

But I would like to increase the number of miscellaneous pollers and other settings, especially MaxHousekeeperDelete and Timeout, without having to restart zabbix_server. Is this possible in current versions?

I did a test, changed MaxHousekeeperDelete = 5000 to 10000, did not restart zabbix_server but ran zabbix_server -R config_cache_reload and then zabbix_server -R housekeeper_execute. I continued to see "slow query: 6.653826 sec," delete from history where itemid = 28656 limit 5000 ""