It caches content.. But the feature set is extremely limited compared to WP, and practically no improvements have been added since the addon was released four years ago. Looking at other alternatives is not a bad idea at this point as they show no interest to improve on XF2.
So far working well on a shared Litespeed server at Veerotech hosting. Server resources have dropped considerably from my older VPS. There was an issue with some desktop/mobile settings with another plugin, but Michael at Litespeed responded very quickly with a fix to resolve the mobile cookies/caching issue on this discussion thread.
As a XenForo developper and big board owner, I worked with the LiteSpeed team to make this addon available to the XenForo customers.
I have been using it for a month on my board realitygaming.fr, and LSCache for XenForo 2 his a must have addon when you own a XenForo forum with LiteSpeed : it's reducing server load and can even reduce the impact of L7 DDOS attacks.