What is a website render blocking resource?
An explanation of blocking resources on websites.
The easiest way to check is to use curl on the command line. On Mac/linux Open up a terminal, on Windows open the Start menu, type cmd in the search box, and press Enter. Then type in:
curl -svo /dev/null https://www.yourdomain.com/your-resource -H "peakhour-debug: givemeheadersplease"
This will return the response headers for your request. You then check for the header:
peakhour-trace
If this header is not present then Peakhour is not currently serving your content. If it is present and has either cdn or cache present in its list of values then Peakhour is serving it from its cache.
An explanation of blocking resources on websites.
An overview of the different types of browser hints and how they help with website performance
An overview of the cache control header sent by websites.
An introduction to cache tags/surrogate keys and how they're used by caching proxies.
An introduction to CDNs (Content Delivery Network)
A quick description of the critical rendering path for browsers
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