NAME
pmTrimNameSpace - prune a performance metrics name space
C SYNOPSIS
#include <pcp/pmapi.h>
int pmTrimNameSpace()
cc ... -lpcp
DESCRIPTION
If the current Performance Metrics Application Programming
Interface (PMAPI) context corresponds to a version 1
archive log of Performance Co-Pilot (PCP) performance met
rics (as collected by pmlogger(1) -V1), then the currently
loaded Performance Metrics Name Space (PMNS), is trimmed
to exclude metrics for which no description can be found
in the archive. The PMNS is further trimmed to remove
empty subtrees that do not contain any performance metric.
Since PCP archives usually contain some subset of all met
rics named in the default PMNS, pmTrimNameSpace effec
tively trims the application's PMNS to contain only the
names of the metrics in the archive.
Since PCP 2.0, pmTrimNameSpace is only needed for dealing
with version 1 archives. Version 2 archives actually
store the "trimmed" PMNS.
Prior to any trimming, the PMNS is restored to the state
as of the completion of the last pmLoadASCIINameSpace(3)
or pmLoadNameSpace(3) or implicit load (in the case of a
host with a version 1 Performance Metric Collector Daemon
(PMCD)) operation, so the effects of consecutive calls to
pmTrimNameSpace with archive contexts are not additive.
If the current PMAPI context corresponds to a host, rather
than an archive, and the host has a version 1 pmcd or a
pmLoadASCIINameSpace(3) or pmLoadNameSpace(3) call was
made, then the PMNS reverts to all names loaded into the
PMNS at the completion of the last pmLoadASCIINameSpace(3)
or pmLoadNameSpace(3) or implicit load operation, i.e. any
trimming is undone.
On success, pmTrimNameSpace returns zero.
SEE ALSO
pmlogger(1), PMAPI(3), pmLoadASCIINameSpace(3), pmLoad
NameSpace(3), pmNewContext(3) and pmns(4).
DIAGNOSTICS
you must have loaded a PMNS using pmLoadASCIINameS
pace(3) or pmLoadNameSpace(3) before calling
pmTrimNameSpace
PM_ERR_NOCONTEXT
the current PMAPI context is invalid
Man(1) output converted with
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