We also had a problem with import in 8.4.
With segm fault 11, with Killed 9 on Mac and with m4getnewpage(): Failed to allocate virtual memory, GetMemPages() failed on Windows server
So the mystandard have gotten a face lift.
So when the backup is triggered, thats the time when a "snapshot" is taken from the system and written down to the backup (.TXT file)...