Chapter 5. PCP metrics

• To list all metrics available through PCP, enter the following command:

  # pminfo

• To list all Satellite metrics and their descriptions, enter the following command:

  # foreman-rake telemetry:metrics

• To list the archived metrics, enter the following command:

  # less /var/log/pcp/pmlogger/satellite.example.com/pmlogger.log

• The pmlogger daemon archives data as received, according to its configuration. To retrieve the name of the active log file, enter the following command:

  # pcp | grep logger

  The output includes the file name of the active log file, for example:

   pmlogger: primary logger: /var/log/pcp/pmlogger/satellite.example.com/20230831.00.10

Procedures

• To print current values of a particular metric, enter the following command:

  # pmval -f 1 disk.partitions.write

  In this example, metric instances on writes to disk partitions are displayed. PCP converts the number of writes to disk partitions from a counter value to a rate value. The -f 1 argument specifies to abbreviate the values to one decimal place.

  Example output:

  metric:    disk.partitions.write
  host:      satellite.example.com
  semantics: cumulative counter (converting to rate)
  units:     count (converting to count / sec)
  samples:   all
  
                   vda1                  vda2                   sr0
                    0.0                  12.0                   0.0
                    0.0                   1.0                   0.0
                    0.0                   1.0                   0.0
                    0.0                   2.0                   0.0

• To print system performance summary every 2 seconds, enter the following command:

  # pmstat -t 2sec

Examples

• To list all metrics that were enabled when the archive file was created, enter the following command:

  # pminfo --archive archive_file

• To view the host and time period covered by an archive file, enter the following command:

  # pmdumplog -l archive_file

• To list disk writes for each partition, over the time period covered by the archive file:

  # pmval --archive /var/log/pcp/pmlogger/satellite.example.com/20230831.00.10 \
    -f 1 disk.partitions.write

• To list disk write operations per partition, with a 2-second interval, over the time period between 14:00 and 14:15:

  # pmval --archive /var/log/pcp/pmlogger/satellite.example.com/20230831.00.10 \
    -d -t 2sec \
    -f 3 disk.partitions.write \
    -S @14:00 -T @14:15

• To list average values of all performance metrics, including the time and value of the minimum/maximum, over the time period between 14:00 and 14:30, and format the values as a table:

  # pmlogsummary /var/log/pcp/pmlogger/satellite.example.com/20230831.00.10 \
    -HlfiImM \
    -S @14:00 \
    -T @14:30 \
    disk.partitions.write \
    mem.freemem

• To display system metrics stored in an archive, starting from 14:00, in an interactive manner similar to the top tool:

  # pcp --archive /var/log/pcp/pmlogger/satellite.example.com/20230831.00.10 \
    -S @14:00 \
    atop

Procedure

• Open the following URL in a browser: http://satellite.example.com:3000