HTTP Caching And Cache Validation Over HTTP/1.1

Most of the resources of an HTML page don’t change from day to day. Yesterday’s CSS files are probably the same ones in place today. The same is true for any included Javascript files. I’m also guessing you don’t swap out images on web pages all that often either. So why make browsers download all these resources again the next time they visit the page?

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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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