Wordpress + Page Builder (wpbakery) = high cpu & memory usage

I run 4 small sites (each with about just 100-300 visits a week) on a 1GB Vultr server, all sites usually run smoothly without any issues.

All 4 sites are built with wpbakery builder and whenever I edit pages or product pages (on a single site) and when the wpbakery modules get loaded, the server cpu and memory usage become high (80-100%).

Sometimes this causes an issue by bringing every site down, showing a ‘Error establishing a database connection’ error on both the front and admin end.

Is this issue purely because my server is too low and I have to upgrade?

I certainly hope not as I just read about how people can run 30x small sites on a single server. I think it’s possible but not when the page builder is causing an issue.