Well I’ve taken the plunge and upgraded to Varnish 4.0 in front of this WP site. It’s early days to draw any firm conclusions, but I shall be monitoring the impact closely. If anything it seems to have slightly reduced my page load times (yay!) without having to implement any of the “Special” VCL logic that I have used in the past to serve up highly optimised varnish only content for when the bots come crawling.
No, this isn’t a method that I use in general to “cheat” and increase my scores on GTMetrix and the like, rather I use it for the search engine crawling bots to boost (in theory at least) my page ranking. Still SEO isn’t really my area of total expertise, but no harm ever came from a quick and responsive piece of hosting infrastructure surely??
Of course the vcl syntax has changed, so we can’t just take our old default.vcl and hang on to it. I’ve based mine mostly upon https://wordpress.org/support/topic/good-varnish-4-defaultvcl which seems to do the job fairly well out of the box.
Well pingdom seems to be impressed at any rate: