Time Machine

Last week, I finally turned on the Time Machine in Mac OS X Leopard (now 10.5.2). Before I started using it, I chose to partition my external hard drive to limit the amount of space that Time Machine was going to use. I first had to copy my existing files to another location before the partition, since doing so erases all of the data on that drive. My internal drive is a mere 80 GB, so I capped my Time Machine partition on the external at 110 GB. That should be more than enough. After I completed the partitioning, I turned on the Time Machine. I dragged what Macworld called the “cartoonishly large slider” into the ON position.

The first backup of my data took quite a while. It had to back up around 30 GB and it took most of the night, around 8 hours or so. Fortunately, only the original backup would take anywhere near that long.

I have to say I am impressed. I am now getting my full money’s worth out of my Leopard upgrade. Time Machine works exactly as advertised, running seamlessly in the background. Now, after a week of backups, I can “travel back in time” as I flip through my folders and files. So cool! I think Time Machine could use a lot more options, though. I don’t like that it wants to back up every hour, take-it-or-leave-it. I don’t want my external drive spinning up and down all the time. I have my music library on the adjacent partition of that drive, and I don’t want it wearing out faster than it should.

Fortunately, you can download a free app that will give you more control. No installation is necessary, either. The app is called TimeMachineEditor and it allows you to easily change the intervals of the backups, without using the Terminal. Using the editor, I changed my backup interval to every six hours. Give it a try, it’s great.

Author: Craig Tisinger


2 thoughts on “Time Machine”

  1. After some experimenting with the TimeMachineEditor app to change my backup intervals, I am not convinced that it works. Over several days, I tried using intervals ranging from 6-12 hours. Despite this, Time Machine was still backing up more often than that. I can’t say it was still hourly, but it certainly was more than I entered. Keep in mind that my trial was in no way scientific, or exact.

    I have decided to delete the program. I have decided to go with a simple Terminal command to change the backup interval. Enter the command below as one long line. (The margins on my blog will wrap the text.)

    sudo defaults write /System/Library/LaunchDaemons/com.apple.backupd-auto StartInterval -int 3600

    Substitute “3600” in the above command with the number of seconds of your choice:

    3600 = 1 hour (Time Machine default)
    7200 = 2 hours
    14400 = 4 hours
    21600 = 6 hours
    28800 = 8 hours
    43200 = 12 hours

    Keep in mind that although you can change the backup interval with this Terminal command, when you later view the Time Machine preferences, the “next backup” time will still display as if the system is st to the default one-hour interval. There seems to be no way around this that I know of.

  2. In the time since I wrote this post and my first comment, I have settled on using manual backups with Time Machine. To do this, simply turn the Time Machine off. On the menu bar, you can click at any time and say “Back up now”. This is easier for me, and I try to do it once a day or so.

    I grew frustrated that when Time Machine was on, it would often inconveniently start up when I woke my computer from sleep. This would happen regardless of the intervals I tried to set with the Terminal commands. I decided, in the end, it would be easier to just back up my data manually.

    I should mention that I’d read in Macworld that if you use Entourage, keep in mind that your data is stored in a single file, and every update to that file from Entourage will cause Time Machine to back up that whole file every hour, if left untamed. Being a new Entourage user, this was also good reason to go manual on the backing up.

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