pmgetderivedcontrol(3) — Linux manual page

PMDERIVEDCONTROL(3)     Library Functions Manual     PMDERIVEDCONTROL(3)

NAME

       pmGetDerivedControl, pmSetDerivedControl  - get and set controls
       for derived metrics

C SYNOPSIS

       #include <pcp/pmapi.h>

       int pmGetDerivedControl(int what, int *valuep);
       int pmSetDerivedControl(int what, int value);

       cc ... -lpcp

DESCRIPTION

       These routines may be used to influence the behaviour of the
       derived metric services that are activated for global derived
       metrics using pmRegisterDerived(3), pmRegisterDerivedMetric(3)
       and pmLoadDerivedConfig(3), or per-context derived metrics using
       pmAddDerived(3) and pmAddDerivedMetric(3).

       The what argument selects a control, the value argument provides
       a value for pmSetDerivedControl and the valuep argument is used
       to return the value for pmGetDerivedControl.

       The what argument has one of the following values:

       PCP_DERIVED_GLOBAL_LIMIT
              The maximum number of global derived metrics that may be
              defined.  The value -1 indicates no limit.

       PCP_DERIVED_CONTEXT_LIMIT
              The maximum number of per-context derived metrics that may
              be defined.  The value -1 indicates no limit.

       PCP_DERIVED_DEBUG_SYNTAX
              Debug diagnostics during parsing of derived metric
              expression.  The value 1 enables the diagnostics, the
              value 0 disables them.

       PCP_DERIVED_DEBUG_SEMANTICS
              Debug diagnostics for semantic checks during the binding
              of metrics in the derived metric expression to the
              available metrics in a new PMAPI context.  The value 1
              enables the diagnostics, the value 0 disables them.

       PCP_DERIVED_DEBUG_EVAL
              Debug diagnostics when derived metrics are used in PMAPI
              operations like pmFetch(3), pmGetChildren(3),
              pmGetChildrenStatus(3), pmLookupDesc(3), pmLookupName(3),
              pmNameAll(3), pmNameID(3) and pmTraversePMNS(3).

RETURN VALUES

       Both routines return 0 on success, else a value less than 0 that
       can be decoded using pmErrStr(3).

SEE ALSO

       PCPIntro(1), pmAddDerived(3), pmAddDerivedMetric(3), PMAPI(3),
       pmErrStr(3), pmLoadDerivedConfig(3), pmRegisterDerived(3),
       pmRegisterDerivedMetric(3) and PMNS(5).

COLOPHON

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Performance Co-Pilot                                 PMDERIVEDCONTROL(3)