The psradm utility changes the operational status of processors. The legal states for the processor are on-line, off-line, and no-intr.
An on-line processor processes LWPs (lightweight processes) and may be interrupted by I/O devices in the system.
An off-line processor does not process any LWPs. Usually, an off-line processor is not interruptible by I/O devices in the system. On some processors or under certain conditions, it may not be possible to disable interrupts for an off-line processor. Thus, the actual effect of being off-line may vary from machine to machine.
A no-intr processor processes LWPs but is not interruptible by I/O devices.
A processor may not be taken off-line if there are LWPs that are bound to the processor. On some architectures, it might not be possible to take certain processors off-line if, for example, the system depends on some resource provided by the processor.
At least one processor in the system must be able to process LWPs. At least one processor must also be able to be interrupted. Since an off-line processor may be interruptible, it is possible to have an operational system with one processor no-intr and all other processors off-line but with one or more accepting interrupts.
If any of the specified processors are powered off, psradm may power on one or more processors.
Only superusers can use the psradm utility.
The following options are supported:
Perform the action on all processors, or as many as possible.
Take the specified processors off-line.
Set the specified processors no-intr.
Bring the specified processors on-line.
Output a message giving the results of each attempted operation.
The following operands are supported:
The processor ID of the processor to be set on-line or off-line or no-intr.
Specify processor_id as an individual processor number (for example, 3), multiple processor numbers separated by spaces (for example, 1 2 3), or a range of processor numbers (for example, 1-4). It is also possible to combine ranges and (individual or multiple) processor_ids (for example, 1‐3 5 7‐8 9).
The following example sets processors 2 and 3 off-line.
psradm -f 2 3
The following example sets processors 1 and 2 no-intr.
psradm -i 1 2
The following example sets all processors on-line.
psradm -a -n
See attributes(5) for descriptions of the following attributes:
|ATTRIBUTE TYPE||ATTRIBUTE VALUE|
The specified processor does not exist in the configuration.
The specified processor could not be taken off-line because it either has LWPs bound to it, is the last on-line processor in the system, or is needed by the system because it provides some essential service.
The specified processor could not be set no-intr because it is the last interruptible processor in the system, or or it is the only processor in the system that can service interrupts needed by the system.
The specified processor is powered off, and it cannot be powered on because some platform-specific resource is unavailable.
The user does not have permission to change processor status.
The specified processor is powered off, and the platform does not support power on of individual processors.