Apple Qmaster 3 - Manual (Page 14)

Rather than actually moving segments, Apple Qmaster tells the service nodes which
segments to read via the network, where to find them, and what to do with them. Below
is an example of how one batch could be processed in an Apple Qmaster system.
Batch submitted by
Compressor or
Apple Qmaster (job request
for frames 1–30)
Cluster controller
divides and distributes
job to available
service nodes
Service node 1 Service node 2 Service node 3
Instructions specifying
locations of source files
and frames 11–20
Instructions specifying
locations of source files
and frames 21–30
Instructions specifying
locations of source files
and frames 01–10
Processed file (frames 1-30)
placed in specified
destination
In distributing batches, Apple Qmaster uses the technology built in to Mac OS X to locate
services in a cluster on the same IP subnet and to dynamically share and receive
information. Because the computers can continually transmit their current processing
availability status, Apple Qmaster can distribute (load-balance) the workload evenly across
the cluster.
14 Chapter 1 Distributed Processing Basics