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Chapter 4 Creating and Administering Clusters 49
To turn off cluster controller services:
1 Open the Apple Qmaster pane in System Preferences.
2 Click Stop Sharing.
3 In the dialog that appears, enter the number of minutes you want controller services to
continue before shutting down, then click OK.
The default is 0 minutes, but you can enter a different number in the field. If you enter
any number greater than 0, a countdown appears next to the Cancel button. The
shutdown delay is provided because some computers may be in the middle of
processing batches, and these could be damaged by a premature shutdown. No new
cluster connections are allowed to occur as the cluster controller is shutting down.
Note: Optionally, you can turn off the controller and just make the node a service
node. To do this, select “Services only” in the “Share this computer as” section.
Using Virtual Clusters to Make the Most of Multiprocessor Computers
If any of the service node computers in your network have multiple processors, you can
adjust the number of instances of processing service, essentially creating virtual clusters
on individual computers. For process-intensive work, having many instances may
increase speed and efficiency, depending on the processing application.
Note: By default, the Apple Qmaster system creates one Rendering service instance for
each processor. Rendering services are for Shake (with Apple Qmaster), Alias Maya, and
other UNIX command-line programs, as opposed to Compressor services, which are
solely for Compressor distributed processing. Consult the documentation that came
with the application to see if using each processor individually is ideal.