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8 Preface Introduction to Distributed Processing
Clusters
When a client sends batches to the Apple Qmaster distributed processing system, all
the processing and subsequent moving of any output files is performed by a group of
Apple Qmaster–configured computers called a cluster. You can create one or more
clusters of service nodes, with one cluster controller included in each cluster. Each
computer in the cluster is connected to the other computers in the cluster through
a network connection.
Note: This illustration provides only one simple example of a cluster. Other possibilities
are described in Chapter 2, “Preparing a Network for Distributed Processing.”
Service Nodes
The service nodes are where the processing work is done. When you assign a group of
service nodes to a cluster, they function as one very powerful computer because all
their resources are shared. If one service node is overloaded or otherwise inaccessible,
another service node is used.
You make a computer available as a service node by configuring it in the
Apple Qmaster pane in System Preferences. The simple steps involved in using
System Preferences to configure a service node are described in Chapter 4, “Creating
and Administering Clusters,” on page 41.
Note: The terms processing and rendering will come up frequently as you read this
document. The term processing is used here generically to cover both rendering (for
Shake, and other frame-based rendering applications) and encoding (or transcoding or
compression) for Compressor. For more information see the Shake User Manual and the
Compressor User Manual .
Cluster
controller
Service
node
Service
node
Service
node
Example of a cluster