Question about Time Machine/Capsule backups

[Tfosorcim]

For Time Machine's "Daily backup" (not talking about the incremental hourly backups), does it do a fresh full backup of the entire drive (minus any directories you exclude in Time Machine's settings)?

I ask because it seems like it does a nearly 600GB backup over Wifi daily to my Time Capsule, and this takes about 8-10hrs, even on my relatively speedy 802.11AC network.

Is this normal? I thought it would be a little more intelligent than that, perhaps cloning a full backup already on the Airport Time Capsule and appending any modifications (additions/deletions) to it.

If this is normal, how does it do incremental (hourly) backups with that much backload?

Thanks

 

[sliceoftoast]

The first backup with time machine is always the longest. Once it has completed that initial backup it should then do the incremental backups. What do you have on the computer that is causing it to backup 600GB+ of data each time?

Do you run any Hypervisors on the computer eg Virtual box / VMware / Parallels ?

Can you confirm that the backup does complete? Or is it trying to backup the same content over and over?

 

[Tfosorcim]

It does finish, but takes literally half the day to do so. Also, I don't have any virtual machines on this machine.

I was able to determine that Time Machine is attempting to backup the entire contents of an external USB 3.0 disk repeatedly (Western Digital MyBook) which contains my iTunes Library, LightRoom Library, Lynda.com media files and CreativeLive media files. Even if I've added nothing to it.

I can't think of any reason why it's trying to do this, unless Time Machine handles USB disks differently than local internal disks.

Until I can figure this out, I'll add the USB drive to the Time Machine exclusion list and will purchase a 3rd party disk cloner to make daily backups of the USB drive to a spare external drive I have. What a mess.

Thanks