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RT Set CPU Pools (Set Pool Sizes) (G Dataflow)

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    Last Modified: January 12, 2018

    Sets the number of CPUs in the CPU pools for automatic load balancing.

    This node creates the System and Timed Structures pools as adjacent pools of contiguous CPUs. The System pool begins at CPU 0 and the Timed Structures pool begins where the System pool ends.

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    Note  

    You cannot use this node to create empty pools or partially overlapping pools.

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    system pool

    Number of CPUs to assign to the System pool.

    This node returns an error if you specify 0 in this input or if the values you specify for system pool and timed structures pool add up to more than the number of CPUs available in the real-time operating system (RTOS).

    If you set both system pool and timed structures pool to -1, this node assigns all CPUs in the RTOS to both pools. If you set either system pool or timed structures pool to -1, this node assigns all remaining CPUs to that pool.

    Default: -1

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    timed structures pool

    Number of CPUs to assign to the Timed Structures pool.

    This node returns an error if you specify 0 in this input or if the values you specify for system pool and timed structures pool add up to more than the number of CPUs available in the real-time operating system (RTOS).

    If you set both system pool and timed structures pool to -1, this node assigns all CPUs in the RTOS to both pools. If you set either system pool or timed structures pool to -1, this node assigns all remaining CPUs to that pool.

    Default: -1

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    error in

    Error conditions that occur before this node runs.

    The node responds to this input according to standard error behavior.

    Standard Error Behavior

    Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

    error in does not contain an error error in contains an error
    If no error occurred before the node runs, the node begins execution normally.

    If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

    If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

    Default: No error

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    assigned CPU pools

    Pool assignment of each CPU.

    Name Description
    System and Timed Structures The CPU is assigned to both the System pool and the Timed Structures pool for automatic load balancing of all threads that are not manually assigned to a particular CPU.
    System The CPU is assigned to the System pool for automatic load balancing of non-Timed-Loop threads.
    Timed Structures The CPU is assigned to the Timed Structures pool for automatic load balancing of Timed Loop threads.
    Reserved The CPU is not assigned to a pool. The CPU is reserved for Timed Loops configured for manual processor assignment.
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    error out

    Error information.

    The node produces this output according to standard error behavior.

    Standard Error Behavior

    Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

    error in does not contain an error error in contains an error
    If no error occurred before the node runs, the node begins execution normally.

    If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

    If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

    Maximizing CPU Utilization

    To maximize processor utilization, you can adjust the number of CPUs to assign to each pool based on the estimation of the proportion of total processing time dedicated to Timed Loops versus system threads. You can estimate the processing load distribution using the RT Get CPU Loads node.

    On an eight-CPU system, if you specify a value of 3 for both system pool and timed structures pool, this node assigns CPU 0 through CPU 2 to the System pool, CPU 3 through CPU 5 to the Timed Structures Pool, and leaves CPU 6 through CPU 7 reserved for use by Timed Loops configured for manual CPU assignment.

    Where This Node Can Run:

    Desktop OS: Windows

    FPGA: Not supported

    Web Server: Not supported in VIs that run in a web application


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