During updates my child sites seem like they’re going down

When from my MainWP Dashboard I select something like “update everything” I notice that my child sites seem to go down for some time during regular wordpress/core/plugin updates.

Not sure why?

In my particular case I have multiple sites running on a (not very powerful) VPS so that may have something to do with it.

Sites always come back up though.

Is there something I’m doing wrong? Maybe if I run it slower or have less actions per minute or something? What’s the best appraoch.

Thanks!