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NAME | C SYNOPSIS | DESCRIPTION | DIAGNOSTICS | COMPATIBILITY | SEE ALSO | COLOPHON |
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PMFETCHARCHIVE(3) Library Functions Manual PMFETCHARCHIVE(3)
pmFetchArchive, - get performance metric values directly from
archives
#include <pcp/pmapi.h>
int pmFetchArchive(pmResult **result);
cc ... -lpcp
The pmFetchArchive API is a variant of the pmFetch(3) interface
that may only be used when the current Performance Metrics Appli‐
cation Programming Interface (PMAPI) context is associated with a
set of archives.
The result is instantiated with all of the metrics (and instances)
from the next archive record, consequently there is no notion of a
list of desired metrics, and the instance profile of the PMAPI
context is ignored.
pmFetchArchive may return a result in which numpmid is zero. This
is a <mark> record that indicates a temporal discontinuity in the
time series of performance metrics. This can happen at the bound‐
ary between archives in a set or if the archive associated with
the current PMAPI context was created using pmlogextract(1) to
concatenate two or more PCP archives, and the <mark> record marks
a point in time between the end of one input archive and the start
of the next input archive.
It is expected that pmFetchArchive will be used to create utili‐
ties that scan sets of archives, while the more common access to
the archives would be via the pmFetch interface.
To skip records within the set of archives, use pmSetMode(3) to
change the collection time within the current PMAPI context, then
call either pmFetchArchive
Note that the result returned by pmFetchArchive is dynamically al‐
located, and must be released using pmFreeResult(3), but not
free(3). See pmFetch(3), and pmFreeResult(3) for further details.
pmFetchArchive returns zero on success.
PM_ERR_NOTARCHIVE
the current PMAPI context is not associated with a set of
archives
Prior to PCP 7.0 the timestamp field in the pmResult struct was a
struct timeval. To support PMAPI transition, the old interface
and semantics can be used if applications are recompiled with
-DPMAPI_VERSION=2.
For a time in PCP 6.x there was a routine with the same semantics
as the current pmFetchArchive called pmFetchHighResArchive, and a
struct with the same definition as the current pmResult struct
called pmResultHighRes, although both are now deprecated and com‐
pile-time support for pmFetchHighResArchive and pmResultHighRes
will be removed in a future release.
PMAPI(3), pmFetch(3), pmFreeResult(3), pmNewContext(3),
pmSetMode(3) and pmTrimNameSpace(3).
This page is part of the PCP (Performance Co-Pilot) project. In‐
formation about the project can be found at ⟨http://www.pcp.io/⟩.
If you have a bug report for this manual page, send it to
pcp@groups.io. This page was obtained from the project's upstream
Git repository ⟨https://github.com/performancecopilot/pcp.git⟩ on
2025-08-11. (At that time, the date of the most recent commit
that was found in the repository was 2025-08-11.) If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page,
or you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a
mail to man-pages@man7.org
Performance Co-Pilot PCP PMFETCHARCHIVE(3)
Pages that refer to this page: pcpintro(3), pmfetch(3), pmgetarchiveend(3), pmregisterderived(3), pmsetmode(3)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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