Masa331 blogging


Hi, i'm Premysl Donat and this is my blog about IT and my life in generall. I work at UOL and in my free time.. well, look at my Github.

Have a good one!


Preconnect and reap the low hanging performance fruit

All credits to this post Eliminating Roundtrips with Preconnect but this preconnect thing is really cool!!

Ok, this is how a fresh request to my homepage looks in terms of performance:

homepage performance without preconnect

See these 93ms? That’s time it takes my browser to initiate connection with font awesome CDN.

And look at this:

homepage performance with preconnect

No 93ms for connection initiation! One fifth of the total time saved. And only thing you need to do is this:

<link rel="preconnect" href="" crossorigin>

With this link you are telling browser you might pull something from As soon as browser gets this link it will initiate a new connection instead of doing it after some CSS requests it. Once CSS requests it, connection is already prepared and that saves a lot of time.

Read the original article and it’s own sources for more in-depth explanation: Eliminating Roundtrips with Preconnect

On SupTasks implemented in commit: d4ddf32