NAME¶
pmTrimNameSpace - prune a performance metrics name space
C SYNOPSIS¶
#include <pcp/pmapi.h>
int pmTrimNameSpace(void);
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 metrics (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 metrics named in the
default PMNS,
pmTrimNameSpace effectively 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), so the
effects of consecutive calls to
pmTrimNameSpace with archive contexts
are
not additive.
If the current PMAPI context corresponds to a host and 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), i.e. any
trimming is undone.
On success,
pmTrimNameSpace returns zero.
SEE ALSO¶
pmlogger(1),
PMAPI(3),
pmLoadASCIINameSpace(3),
pmLoadNameSpace(3),
pmNewContext(3) and
pmns(5).
DIAGNOSTICS¶
- PM_ERR_NOPMNS
- you must have loaded a PMNS using pmLoadASCIINameSpace(3) or
pmLoadNameSpace(3) before calling pmTrimNameSpace
- PM_ERR_NOCONTEXT
- the current PMAPI context is invalid
