On Arch based distributions when Unrar a file it doesn’t slow my laptop but on Ubuntu based it gets unusable

I don’t understand the reason for this behavior.

I use Usenet and when it unrars the files my laptop starts stuttering, lagging and sometimes freezes till it’s fully unrared.

On Manjaro it works so much better. There is barely any lag.

Hope someone can explain it to me.

Btw always had better experience using arch based distributions than Ubuntu. Again have no idea why.