What does Time Machine back up?

The incremental backups only include the files that have changed.

It doesn't look that way when you browse Time Machine - each date looks as if it's a complete backup. However, it's actually pointing to the one copy that's kept of each file/version.

Barney63 said:

I have hardly used it today and it is doing an hourly backup now of 7gb!
Why so much I've only been browsing the forums and been on Facebook for 10 minutes.

Barney

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Do you use a Virtual Machine for Windows (VMware Fusion or Parallels)?

If so, you need to exclude the vm from the TimeMachine backup.

Barney63 said:

I use parallels.
I will exclude it in the morning.
Thanks.

Barney

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Yeah ... anytime you run Windows, that file (container) changes and will be in the backup ... and it can be 10-30GB in size. You probably don't want to be constantly backing that up.

Barney63 said:

I use parallels.
I will exclude it in the morning.
Thanks.

Barney

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Do you care if your virtual machines are not backed up?

Mine are mission-critical. And yes, they get rather large. By all means, when you set up a virtual machine, set it up so that the virtual disks are split into small (typically 2GB) chunks. That minimizes the amount of backing-up that's needed.

But think twice about excluding them from your backup.

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hfg said:

Do you use a Virtual Machine for Windows (VMware Fusion or Parallels)?

If so, you need to exclude the vm from the TimeMachine backup.

Click to expand...

That's dangerous advice.

My Windows virtual machines are backed up outside of time machine. I keep the files used by Windows in my Mac file space so they are backed up continually. Just because I don't use time machine to back it up doesn't mean it doesn't get backed up.

I periodically "clone" my vm when I think it necessary. My Windows vm is over 40GB and I usually have it running all the time. If I let TimeMachine include it in the hourly backup, the backup would never stop.

Barney63 said:

I've found the Windows7.pvm and excluded that, but it is only 6.91GB.
The backup is still doing 62.67GB, where is all that coming from?
I haven't even been on the laptop for any files to have changed!
I also noticed when I logged on Time Machine asked me if I wanted to use the TC as the name had changed or something.

Barney

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"name had changed or something" is probably the reason why it does a full backup again.