Platform Peace

One problem I ran into with my new Time Machine setup was that my large virtual machine disk files were aggressively being backed every time they changed.  Since each virtual machine is extremely large (multiple GBs each) and since Time Machine backs up an entire file each time it changes, I was quickly eating up lots of space on my external drive.  Also, since Time Machine had to backup what turned out to be 20+ GBs nearly every hour, Time Machine backups weren’t exactly transparent.  I certainly noticed based on CPU and disk activity that backups were in progress.

Thankfully, there was an easy fix.  As mentioned in the previous entry, Time Machine lets you exclude specific disks, directories, and files from backups.  I keep all my Virtual Machines in "~/Virtual Machines" so I simply added that directory to the exclusion list.

However, one more step remained.  I wanted to free up all the space taken by the virtual machine backups before I noticed the problem.  I opened Finder and navigated to my Virtual Machines directory (actually I invoked Quicksilver and typed "virt" + enter).  I then launched Time Machine (Quicsilver + "Tim" + enter).  From the Gear menu button in the Finder, I selected "Delete All Backups of …" for each of the files and directories I wanted to remove. 

Time Machine will prompt you for confirmation and, if you are not running as a privileged user, will also prompt you for credentials. 

Problem solved.  I excluded my virtual machine backups from Time Machine and freed up close to 100 GBs of space from my drive.