XF 1.5 Are there any advice to let the forum run faster?

[msibm]

After converting from vBulletin 3.8.6, many users complain that the forum is obviously slower than before.
How to disable some functions to let it faster from the point of users' experience?

 

[Fred.]

Define a caching method
https://xenforo.com/help/cache/

Memcached works great for me.

BD cache is also awesome
https://xenforo.com/community/resources/bd-cache.2763/