CPU binding of HAD for HP-UX and Solaris
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CPU binding of HAD for HP-UX and Solaris

In certain situations, the HP-UX operating system may assign the CPU to high priority interrupts or other higher priority processes like HAD. In this scenario, HAD cannot function until it gets scheduled. To overcome this issue, VCS provide the option of running HAD on a specific processor. This way you can shield HAD from other high priority processes.

In certain situations, the Solaris operating systems may assign the CPU to high priority interrupt thread to the CPU on which HAD is running, thereby interrupting HAD. In this scenario, HAD cannot function until the interrupt handler completes its operation. To overcome this issue, VCS provides the option of running HAD on a specific processor. VCS masks off all interrupts on that processor set. Configure HAD to run on a specific processor by setting the CPUBinding attribute.

See System attributes.

To modify the CPUBinding attribute

• Type the following command:

hasys -modify sys1 CPUBinding BindTo CPUNUM|NONE|ANY [CPUNum 
number]
 
  


 The value NONE indicates HAD does not use CPU binding.



 The value ANY indicates that HAD binds to any available CPU.



 The value CPUNUM indicates that HAD binds to CPU specified in the CPUNum attribute.



 The variable number specifies the number of the CPU.


  Note that you cannot use the -add, -update, or -delete [-keys] options for the hasys -modify command to modify the CPUBinding attribute.