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Controlling SMP CPU (Processor) Affinity?

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The Question is:

When I do a SHOW CPU/FULL 1 command on a multiprocessor AlphaServer system, it
 states that there are no processes which can only execute on this CPU.
I used the Ask OpenVMS service on the OpenVMS web site and it pointed me to an
 article which described BIND in SYS$EXAMPLES: )which doesn't exist on my
 system, however, it did specificially mentioned a VAX computer and not an
 Alpha computer).
How do I have a process run on a specific CPU on an Alpha system running
 OpenVMS V6.2?

The Answer is :

  The OpenVMS Wizard generally (strongly) discourages the use of the
  CPU (processor) affinity system services, though the services are
  available.  (This is simply due to the scheduling constraints that
  can easily arise when using hard affinity.)  For details on these
  and on other system service calls, please see the OpenVMS system
  service reference documentation and please also see the "affinity"
  references in the index of the OpenVMS Programming Concepts manual.
  To entirely reserve a CPU to one or more processes, set up a user
  capability for all (other) processors and all processes except for
  the process(es) that are to run on the dedicated processor.
  You will also want to upgrade, as OpenVMS Alpha V6.2 is rather old, and
  as the processor affinity mechanisms were added in OpenVMS Alpha V7.0.
  On older OpenVMS releases, the unsupported and undocumented $DIAGNOSE
  call is potentially interesting -- this call is used by CPU diagnostics.
  This call is not recommended.

answer written or last revised on ( 6-SEP-2001 )

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