Following up with the last post, I decided to make my website even faster (which probably doesn't make a difference anymore).
My pages (HTML only) were about 21KB (without compression), but 11KB of those consisted of an SVG
that appeared in all of them: the logo. The logo wasn't requested from a different static file
because I needed to modify it using CSS (so that colors would change when switching to the dark
theme) and, at the time, I thought inlining was the only option to allow that. However,
investigating a little I found out there are alternatives to inlining: we can take advantage of
the use tag of SVGs to "inline" an SVG from a different URL. By using that, my pages
are now around 10KB of size (plus the statics files, which have a total size of 37KB for the pages
without MathJax).
Considering that the favicon.ico is already 15KB, 47KB for a page is very good!
Nevertheless, I wanted to reduce it even more1. I looked
into browser caching and liked the idea. I'll explain the basics. When our browser sends a request
for a certain resource (URL/file), the server that responds can add information that tells the
browser how long it should keep the file for. If the next time you browse that site and need the
file again the file hasn't "expired", your browser will not request it, but instead make use of
the copy previously downloaded. This reduces the number of requests made and the bandwidth
used.
The only problem with browser caching is that if the contents of a certain file change, your users
will not see those until their copies expire. We want to maximize the time a file is used for
before requesting it again while minimizing the time between update checks (unless our static
files never change). To solve that, I used Hugo's
Pipes, which allows you to add the SHA256 sum of a static file to its name automatically (and
all the places where the file is referenced). Now when downloading the CSS file, your browser is
requesting https://oscarbenedito.com/css/style.min.<SHA256>.css, which will
(highly probably) change when the contents change. Since the URL will be different, the browser
will request the new file.
I found out that SVG files where not being compressed by default2. So I also enabled that!
My webpage is ridiculously small and all these optimizations aren't that important. However, it is fun to learn about all of this and it can also be helpful if in the future I have a site with bigger static files (or someone reading this has!).