To connect you to information in real time, it’s important for Twitter to be fast. That’s why we’ve been reviewing our entire technology stack to optimize for speed.
To improve the twitter.com experience for everyone, we've been working to take back control of our front-end performance by moving the rendering to the server. This has allowed us to drop our initial page load times to 1/5th of what they were previously and reduce differences in performance across browsers.
This week, we rolled out the re-architected version of one of our most visited pages, the Tweet permalink page. We’ll continue to roll out this new framework to the rest of the site in the coming weeks, so we'd like to take you on a tour of some of the improvements.
No more #!
The first thing that you might notice is that permalink URLs are now simpler: they no longer use the hashbang (#!). While hashbang-style URLs have a handful of limitations, our primary reason for this change is to improve initial page-load performance.
Reducing time to first tweet
Before starting any of this work we added instrumentation to find the performance pain points and identify which categories of users we could serve better. The most important metric we used was "time to first Tweet". This is a measurement we took from a sample of users, (using the Navigation Timing API) of the amount of time it takes from navigation (clicking the link) to viewing the first Tweet on each page's timeline. The metric gives us a good idea of how snappy the site feels.
Loading only what we need
We're currently rolling out this new architecture across the site. Once our pages are running on this new foundation, we will do more to further improve performance. For example, we will implement the History API to allow partial page reloads in browsers that support it, and begin to overhaul the server side of the application.
@danwrong yey! The future is coming and it looks just like the past, but more good underneath.— Tom Lea (@cwninja) May 23, 2012
-Dan Webb, Engineering Manager, Web Core team (@danwrong)