Maybe I haven't been specific enough. I meant, usually, if we run a long maintenance, then logged in users are blocked with a message "server busy". So using parallel maintenance should not block users with "server busy"?
I would like to know what BackgroundHALShouldPause does, and how to use it. While it's listed in the HAL Primitives report, it is not used in source code and it doesn't appear in the LMS HAL...