Just as Time Machine was beginning to grow on me as a viable backup option I ran into my first annoyance. And it is annoying.
Until now Time Machine ran almost unnoticed by me. But tonight I had a Parallels VM open for several hours. The good news is that Time Machine didn’t seem to be bothered by this.
But then I shut down the VM and Time Machine’s hourly backup time rolled around. Time Machine had 12.9GB to back up, almost all of it was that VM. I was playing music in iTunes like I often do and it sounded like a record skipping (to those of you too young to remember vinyl think fingernails on a blackboard). The skipping is what caught my attention. The CPU wasn’t pinned (although heavily used) but between that and reading the disk iTunes was affected. I was typing at the time and that seemed unaffected. The backupd process was showing around 70% in activity monitor.
Since I don’t really care about backing up the VM’s (well, I do – but not frequently so I’ll come up with an alternative) I excluded them from Time Machine.
To do this go into System Preferences and select Time Machine. Then click the Options button and click the + button. Browse to and select the location of the Parallels VMs.
Then click the exclude button to save it to the exclude list.
This doesn’t remove them from existing backups, but future backups won’t have them.