Aperture, OS X 10.5.2 and Time Machine

[Paul Sargent]

On Thu, Feb 28, 2008 at 2:44 AM, Scott Lewis <sglewis at mac.com> wrote:

>  I guess basically, I'm hoping a file system expert can provide a clear
>  tutorial of how these hard links work, and even better, provide a way
>  to estimate how much space a particular time machine backup occupies,
>  ie it represents 400gb of backups but since it was incremental, it's
>  only using 20gb of space and the rest are hard links. How on earth can
>  you tell?

It's really difficult to tell because, as you say, all of the file
tools treat hardlinks as proper files (Well.... they are, but that's a
whole new discussion).

Your best bet might be to look at the hidden backup log that's in the
top of each timestamped directory in the Time machine backup. I'm not
at my Mac, but it's something like
/Volumes/TimeMachineBackupDisk/backups.db/MachineName/TimeStamp/.backup.log.
This will tell you how much backupd decided it needed to backup each
time.

Sidenote: I tried writing some scripts to show me which files were
unique to a particular backup, but it became really complex, really
quickly, especially dealing with hard linked directories. (Q: How many
links does a directory have? A:1 for the directory it's in, 1 for the
self reference '.' and '1' for the parent reference '..' in each
directory under it. Then add the number of hard linked version of it
*Brain goes boom*)