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+1 vote
in Q2A Core by
@scott, If  question is cached and then someone posts answer or comment then will it be immediately purged and updated in cache? I do see setting admin->caching->Cache question pages for: 30 min.....or will it be updated after 30min?

1 Answer

+3 votes
No, the cache is not immediately purged. At the moment I don't think it's a big issue because caching only works for logged-out users. We also have the option to start caching after n days which means newer posts, which are likely to have more 'write' activity, are not cached.

In the next version I will work on allowing some caching for logged-in users (which means rewriting a lot of SQL queries) so will probably need to add it then.
I think that we definitely need some caching for logged-in users.
@Ok. It will be good if  only purged items are updated immediately. This will help if some question is updated many time in a day and it is frequently accessed on site.

I dont know if our implementation is similar to wordpress cache but when you get time please look into below two plugins, you may get some other ideas.
@Ankhamax When I tested on my site, the vast majority of visitors were not logged in. Solving that case first makes a bigger difference.

The problem at the moment is that the queries to fetch questions also fetch the votes/favorites for the logged in user, which cannot be cached. To change that is a lot of work.