Ruby on Rails is fast

Of course, this title is obviously too blunt. Still, when I see applications being developed on supposedly fast languages such as Java that perform terribly slow it makes me wonder.

Today I had to fix an issue with the slowness of an overview page inside a product I wrote using Rails. I don’t like pagination (it’s a workaround), but I wasn’t expecting pages with over 700 items. The page with items stored in a traditional database was performing somewhat slow: it took about 6 seconds to load. The fix however took me less than half an hour (including searching the docs) from idea to execution and deployment on production (writing this post took me longer):

<% cache(item) do %>
  old view code to render the item
<% end %>

Passing the item itself to the cache ensures that the cache gets invalidated when the item is updated. The page load it is still kinda heavy, with 500ms of load time, but this is acceptable for its size.

Features like this make Rails not only a super fast way to realise your projects, but also makes it perform quite well in real-world production.

Read more on Rails’ fragment caching in the docs, some real world statistics from Basecamp and the original post by DHH in which he explains Russian Doll caching