Bitrix + memcached does not cache, why?

Question

linux

1. Memcached is installed
2. Bitrix determines the type of caching on the "performance panel"
3. Memcached itself hangs as a daemon
The problem is long page generation when requesting a product catalog. When the "debug" mode is enabled, it shows the cache size 0 b, the type of caching is enabled on the component.
Or is it just not enough to enable caching and insert auto Bitrix?
The question is - what actions need to be performed with Bitrix in order for caching to start?
The system is ubuntu 14, bitrix 14.5, there are 3 more sites on the server (2 on pure puff, 1 on bitrex), the CPU load is constant around 80 on 2 cores (htop), the main consumer is mysql, I tested queries to the database, the answers are in within reason.

Answer 1

It seems that you need to make changes to the dbconn.php file and something else:
https://dev.1c-bitrix.ru/learning/course/?COURSE_I...
https://dev.1c-bitrix.ru/api_help/perfmon /perfmon_...
https://dev.1c-bitrix.ru/learning/course/?COURSE_I...