By serving up static HTML as the basis of the page, the NodeJS app is also much faster loading the base page - 240ms vs 3200ms.
Here's the detailed breakdown:
* The NodeJS app renders client-side using Backbone, and uses MongoDB for a datastore. The Rails app renders server-side, and uses Postgres for a datastore. The NodeJS app renders 20 results, the Rails app renders 10 results. The Rails app additionally renders a timeline graph as well as determining the count of results upfront.
Update: I had a request to use New Relic to explain why the Rails app is so slow. Here's a breakdown from a Transaction Trace: