Earlier today Google began it’s full roll out of the Google Speed Update (having quietly updated this blog post from January).
Google Speed Update only affects websites that deliver the slowest experience to web users and will only affect a small percentage of queries. It applies the same standard to all web pages, regardless of technologies in use on the website or server. Google has made clear in the above blog the search intent is still the primary lead, so a slower page may still rank better than a fast page should it offer the best result – though belts and braces (and experience) say do what the update tells you.
If you are interested in improve your page speed, Google suggests the following tools from its own arsenal: Lighthouse, an automated tool within the Chrome Developer Tools for pagespeed and auditing page quality and PageSpeed Insights, a tool which suggests possible improvements both for speed and UX.
Further reading, I wrote this piece about speeding up wordpress using CDNs and Caching.