For several weeks my timemachine backup failed, being stuck in ‘inprogress’ with lots of disk activity occurring. The culprit turned out to be spotlight, trying to index the backupdisk while timemachine was trying to backup to it. adding my backupdisk in the ‘privacy’ tab of spotlight resolved the problem.
in the process list, processes with ‘md’ in the name, like mds_stores and ‘mds’ and mdworker_shared belong to spotlight.
Timemachine is handled by ‘backupd’.
tmutil is the commandline tool for managing timemachine. mdutil is the commandline tool for managing spotlight.
