Resource Limitations



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Resource Limitations

Available memory limits the maximum size and number of outstanding messages the system can handle. The number of file descriptors (I/O channels) available to a process limits the number of direct route connections a task can establish to other tasks, and the number of tasks a single pvmd can manage. The number of processes allowed to a user limits the number of tasks that can run on a single host, and so on.

An important thing to know is that you may not see a message when you reach a resource limit. PVM tries to return an error code to the offending task and continue operation, but can't recover from certain events (running out of memory is the worst).

See §gif for more information on how resource limits affect PVM.