Remember login vs User session lifetime

Can someone explain to me how the "Remember login" setting interacts with the "User session lifetime" setting? If I set the "Remember period" to 7 days and the "User session lifetime" to 120 minutes, when will the user be logged out of their account (provided they click the "stay logged in" box)? After 7 days or 120 minutes?

I don't understand how these 2 values coexist.

Thanks.

Got it. Thanks.

If I leave "User session lifetime" blank does that mean Amember will never log the user off?

Is there a way to disable this function?

Also, how is this done? Is this a cron job that Amember runs? It appears to run every minute.