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The Job Slots (or Process Slots) for a Worker determine how many processes a given Worker can run at a given time. The By default, the number of Job Slots have no direct relation is set to the number of processor cores on a given machine. It , but this relationship is not required and can easily be changed so that the number of slots is different. For example, it is often desirable when using a multi-threaded renderer like Maya to have the Worker run 1 instance (or process) at a time, using all the cores for that instance - so that would be a single slot with 8 cores (on an 8-core machine). On the other hand, if we want to run many single-threaded processes that each require a few resources, you may want to set the Worker to have 4 or 8 Job Slots available.
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