by Stuart Mealor.
The easiest way to quickly stop the Backups running is just to switch the Active status to Disabled, or Manual. In Moodle 2.x look under:
Home > Site administration > Courses > Backups > Automated backup setup
Manual is good, because you can then trigger a Cron manually and view the output, which might show you where the problem is. It's most likely backing up too much, but trouble-shooting is the next stage after stopping it eh?
Stu