Caching on Pantheon

Pantheon automatically includes a ‘caching’ plugin for the site. This is different than the cache on your personal web browser.

Here are some technical details about how the website works in case you are interested:

• Normally, when someone visits a page on a site built by WordPress, their browser requests the page from the web server. Then, WordPress puts the page together by querying the content from the database that is on the web server. This is performance intensive because it requires multiple calls to the database and the page is generated on the fly.

• With the plugin that Pantheon (our host) uses, a copy of each page is saved, and when a browser requests a page, the saved copy is served to them. This improves performance (pages load faster) because you avoid the on-the-fly generation.

• The technical name for this is a Varnish Edge Cache.

The way the caching is set up by default is a page is saved in the cache for at most 10 minutes. So, any changes you make might take up to 10 minutes to be seen.

We have installed Pantheon Advanced Page Cache on the UWSS site. This should clear the cache of a page when it is updated.