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Other Possible Components of a Distributed Processing Network
A distributed processing network can consist of as few as one or two computers, whereas
a high-volume network may include many computers, an Xserve system and Xserve
cluster nodes in a rack, and high-speed networking infrastructures. You can scale up a
distributed processing system as your workload demands by adding features and devices
to the network that supports it.
There are many ways to expand the capacity of a distributed processing network. You
could include any of the following.
• High-speed switch and cables: A 100Base-T or Gigabit Ethernet switch and compatible
cables to allow your data to move over the LAN at maximum speed.
• Multiple clients: Multiple client computers can use the services of the same cluster. And,
you can have multiple client applications on the same client computer, using the same
cluster.
• Multiple clusters: Depending on how extensive your network is and how many clients
it needs to serve, you may want to divide up available computers and create more than
one cluster to serve various clients. (Users select the cluster they want to send a batch
to when they submit the batch.)
• Multiple service nodes: In general, more service nodes mean more processing power.
In deciding how many service nodes to have in a cluster, consider the ratio of data
movement time to computing time. If the processing demand is greater than the
network demand required to move job segments throughout the cluster, as is the case
with rendering, more service nodes are a good idea. If the computing load, per job, is
closer to the network load, having a smaller number of service nodes per cluster may
be more efficient. If you are using the Apple Qmaster distributed processing system
with applications other than Shake or Compressor, consult the application’s user manual
on how to optimize the number of service nodes.
• Storage device: A storage device, such as a remote disk or group of disk arrays, can be
used as cluster scratch storage, which is a place for short-term storage of temporary
data generated by the cluster controller, clients, and service nodes. (You set the scratch
storage location in the Apple Qmaster Sharing window of Compressor. See About
Advanced Settings in the Apple Qmaster Sharing Window and Using Cluster Storage
for more information.) Alternatively, a storage device can be used as a final destination
for the files after they are processed.
For more information, see Examples of a Distributed Processing Network.
Getting Started Quickly Using This Computer Plus
Using This Computer Plus in Compressor gives you an easy way to take advantage of the
distributed processing capabilities offered by Apple Qmaster without requiring a lot of
knowledge about how clusters are configured, how to set up file sharing, and so on.
358 Chapter 29 Apple Qmaster and Distributed Processing