Alexey
I don’t think Rails provides time based caching. I also do not think
it’s needed. What are you trying to accomplish?
Lets say you have a page with list of products that you want to cache.
The cache only needs to be updated if one of the products changes.
Caching the page for an arbitrary amount of time is unnecessary.
If you really need a time based cache, you could just use a cache,
then set the expire action as a cron job that runs every 15 minutes.
But really, infinite caching with proper expiration is the way to go.