With the release of Leoaprd many people have started to use Time Machine. Yet, when it runs in the background, it slows down your machine’s performance. Especially when you work with real-time applications like FCP, it can lead to dropped frames when it runs.

So better than setting it to automatic mode and let it run every hour, we can schedule our Time Machine backups. While there are some nice GUI applications available for this task, this article explains how you can do this using onboard tools like AppleScript and iCal.

This is a nice and easy one, so don’t be afraid to go on reading.

First, we need to set up Time Machine in System Preferences:

Time Machine Settings in System Preferences

This screenshot assumes that you have already chosen the backup volume. Under Options choose files, folder, and/or volumes which you don’t want to backup.
The most important part, though, is that you TURN OFF Time Machine. Otherwise it would run every hour, which we are trying to change here.

After this, we can invoke Time Machine manually, which you can either do by using the Time Machine menulet:

Time Machine in the menulet

or by opening the Terminal application in /Applications/Utilities/Terminal, and typing


Either of this would trigger your Time Machine backup, while both methods would invoke the latter command in the background.

Now let’s use this command and make it executable by iCal.

First, open /Applications/AppleScript/Script Editor, then enter the following text and save the file as a script called Backup:

tell application "Terminal"
do shell script "/System/Library/CoreServices/backupd.bundle/Contents/Resources/backupd-helper"
end tell

This should now look like this:

Time Machine Backup Script in Script Editor

Hit Run in Script Editor to see if your little application works.

If it does, you can now go to iCal and open its Settings panel.
Make sure, that in the advanced panel the options “Turn off all alarms” and “Turn off alarms only when iCal is not open” are not active.
This makes sure, that your backups will run no matter if iCal is running or not.

Yet, the whole story only works as long as your current user is logged in to the GUI of your machine, so you might want to activate automatic login for your user (or you don’t, as you like).

Now create a new iCal event (which might be created in a dedicated Backup calendar):

Time Machine backup as iCal event

The trick here is to set up an alarm and use “run script” as the alarm action. Now select your Apple Script which you have just created and save your choice.
Schedule this event to a time at which you don’t work, and set up the recurrence rule.

Voil! You’re done!

Posted on by André Aulich. This entry was posted in Mac OS X.

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