HP Instant Capacity User's Guide for Version 9.x

A.9 Instant Capacity Compatibility with Processor Sets (HP-UX)
A.9.1 Overview
The Instant Capacity software successfully coexists with processor sets (psets).
To coexist with psets, the Instant Capacity software activates and deactivates cores in only the
default processor set. Cores in nondefault processor sets are not activated or deactivated.
NOTE: There must be at least one core in the default processor set. The last remaining core in
the default processor set is unavailable for deactivation.
A.9.2 Scope of the Instant Capacity Software Interacting with psets
The Instant Capacity software does not provide any additional functionality to specifically
support adding or removing cores from a specific pset.
A.9.3 psets on nPars
In an nPar environment where psets are present, the Instant Capacity software activates and
deactivates cores in only the default pset.
Cores can be manually migrated to the default pset for purposes of deactivation, or from the
default pset to other psets after activation.
A.9.4 psets on vPars
In a vPar environment, the Instant Capacity software passes the request for a core activation or
deactivation to the vparmodify command.
With vPars version A.04.01 or later, vPars is pset-aware to some extent. When adding cores to a
running vPar, a core is always added to the default pset; thereafter, the core can be moved to
another pset. When removing cores, vparmodify chooses cores from the default pset first. If
not enough exist in the default pset to satisfy the request, vparmodify chooses the remaining
cores arbitrarily without regard to pset membership.
With vPars versions earlier than A.04, no special consideration is given to psets from the
vparmodify command’s perspective. Therefore, when using vPars, cores in nondefault psets
must be bound cores. Otherwise, a core designated for deactivation by vparmodify might be
selected from an unexpected pset.
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