Ubuntu Manpage: pmloglabel - check and repair a performance metrics archive label

NAME

       pmloglabel - check and repair a performance metrics archive label

SYNOPSIS

       pmloglabel [-Llsv] [-h hostname] [-p pid] [-V version] [-Z timezone] archive

DESCRIPTION

pmloglabel verifies, reports on, and can modify all details of the labels in each of the
files of a Performance Co-Pilot (PCP) archive log. The archive log has the base name
archive and must have been previously created using pmlogger(1).

Each of the files in a PCP archive (metadata, temporal index, and one or more data
volumes) must contain a valid label at the start, else the PCP tools will refuse to open
the archive at all.

Thus, the primary function of pmloglabel is to be able to repair any inconsistent or
corrupt label fields, such that the entire archive is not lost. It will not check the
remainder of the archive, but it will give you a fighting chance to recover otherwise lost
data. Together, pmloglabel and pmlogextract are able to produce a valid PCP archive from
many forms of corruption.

Note that if the temporal index is found to be corrupt, the "*.index" file can be safely
moved aside and the archive will still be accessible, however retrievals may take longer
without the index.

The options control the specific information to be reported, or the specific fields to be
modified:

-h Modify the logged hostname in the archive label, for all files in the archive.

-l Dump out the archive label, showing the log format version, the time and date for the
start and (current) end of the archive, and the host from which the performance
metrics values were collected.

-L Like -l, just a little more verbose, showing also the timezone and creator process
identifier from the archive label.

-p Set the process identifier stored in the archive label to pid, for all files in the
archive.

-s Rewrite the sentinel values which precede and follow the archive label, for all files
in the archive.

-v Verbose mode. Additional progress information is produced at each step.

-V Stamp the version number into the magic number field at the start of the archive
label, for all files in the archive.

-Z Changes the timezone in the archive labels to timezone in the format of the
environment variable TZ as described in environ(7).

EXAMPLES

       The  following demonstrates the use of pmloglabel in finding and then correcting a corrupt
       field (PID) in the label of the temporal index of an archive named "20080125".

                 $ pmdumplog -l 20080125
                 pmdumplog: Cannot open archive "20080125": Illegal label record at start of a PCP archive log file
                 $ pmloglabel 20080125
                 Mismatched PID (5264/5011) between temporal index and data volume 0
                 $ pmloglabel -p 5264 20080125
                 $ pmdumplog -l 20080125
                 Log Label (Log Format Version 2)
                 Performance metrics from host fw1
                   commencing Fri Jan 25 00:10:09.341 2008
                   ending     Sat Jan 26 00:09:54.344 2008

EXIT STATUS

       pmloglabel exits with status 0 if the archive labels are clean.  If  invoked  incorrectly,
       the  exit  status  will  be 1.  If corruption is detected and still exists at the end, the
       exit status will be 2.  If requested to write out the archive labels, and some  aspect  of
       that write out fails, then the exit status will be 3.

FILES

       $PCP_LOG_DIR/pmlogger/hostname
                 Default   directory  for  PCP  archives  containing  performance  metric  values
                 collected from the host hostname.

PCP ENVIRONMENT

       Environment variables with the prefix PCP_ are used to parameterize the file and directory
       names used by PCP.  On each installation, the file /etc/pcp.conf contains the local values
       for these variables.  The $PCP_CONF  variable  may  be  used  to  specify  an  alternative
       configuration file, as described in pcp.conf(5).