[Ham-Mac] Manual Deletion of Older OS X Time Machine Backups

[David Kelly]

On Jul 21, 2011, at 12:56 PM, Dick Kriss wrote:

> The Kicker or Catch-22 are the key words in the first line "...To delete all backups of one or more items" and that means you can delete ALL copies of specific files in all of the backups.  I was
> wanting to delete all files on a given date and that will not work.   
> 
> I can see where the procedure could buy you some elbow room if you had all kinds of movies 
> stored and you also have them on another backup drive. Then selecting all of the movies would delete them from the TM backup.  

Yes, I saw the above and didn't think that was what the O.P. was asking to do.

Stated another way, when Time Machine fills its disk it performs a kind of garbage collection. For most recent days it keeps snapshots by the hour. When it performs this "garbage collection" it rolls hourly snapshots into daily snapshots. And going farther back it rolls dailies into weeklies. And eventually weeklies into monthlies. *This* is what takes a non-trivial amount of time, and what I understood the O.P. was asking to be able to do on-demand rather than suddenly need to be done for an hourly backup.

I once maxed my 600GB Time Machine repository and swear it took my 2.8 GHz quad CPU Mac Pro over 48 hours to do its housekeeping. On SATA drives installed inside the machine. When it was finished I was disappointed to find it had discarded a couple of years of backups.

Time Machine is great for what it does but there is a need for supplemental utilities that one might roll off permanent archives.

--
David Kelly N4HHE, dkelly at HiWAAY.net
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Whom computers would destroy, they must first drive mad.