The Performance Of HTTP Requests Over HTTP/1.1

How much do you know about HTTP? I’m sure you know it’s at the front of every URL, whether you type it or not, but do you know what version of HTTP your site uses or the difference in performance by switching to HTTPS?

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How To Leverage DNS Caching

One of the recurring themes in this series and many articles about performance is caching. Serving cached content often leads to significant performance improvements as it saves round trips and thus time over a network.

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How DNS Lookups Affect Website Performance

Resolving a domain name into an IP address is probably not a performance bottleneck for your site. To be honest, there are limited performance gains to be had with DNS lookups. That said, I think there are some good reasons to understand DNS better both in general and in terms of performance.

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Time To First Byte (TTFB)

Over the years as this site has grown in both content and traffic and as my relative knowledge about developing performant websites hasn’t, I’ve been disappointed in the performance of this site. I have worked to improve the situation from time to time only to let it slide again when I’d move to a new host and as I’ve let my coding practices lag industry best practices.

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Performance Testing—Tools And Waterfall Diagrams

Not all performance improvements are equal. If your CSS file loads in 100ms, but your images take 20 seconds to load, it makes more sense to focus on the images before trying to squeeze extra performance out of an already performant CSS file. In order to know where to spend your time to get the most in return for your effort, you need to know how your site is currently performing.

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