gpperfmon_install

Installs the gpperfmon database, which is used by Greenplum Command Center, and optionally enables the data collection agents.

Synopsis

  1. gpperfmon_install --port <gpdb_port> 
  2.       [--enable --password <gpmon_password> [--pgpass <path_to_file>]]
  3.       [--verbose]
  5. gpperfmon_install --help | -h | -?

Description

The gpperfmon_install utility automates the steps required to enable the data collection agents. You must be the Greenplum Database system user (gpadmin) to run this utility. The --port option is required. When using the --enable option, the --password option is also required. Use the --port option to supply the port of the Greenplum Database master instance. If using the --enable option, Greenplum Database must be restarted after the utility completes.

When run without the --enable option, the utility just creates the gpperfmon database (the database used to store system metrics collected by the data collection agents). When run with the --enable option, the utility also runs the following additional tasks necessary to enable the performance monitor data collection agents:

  1. Creates the gpmon superuser role in Greenplum Database. The data collection agents require this role to connect to the database and write their data. The gpmon superuser role uses MD5-encrypted password authentication by default. Use the --password option to set the gpmon superuser’s password.

  2. Updates the $MASTER_DATA_DIRECTORY/pg_hba.conf file. The utility adds these lines to the host-based authentication file (pg_hba.conf):

    1. local      gpperfmon     gpmon                 md5
    2. host       all           gpmon  127.0.0.1/28   md5
    3. host       all           gpmon  ::1/128        md5

    The second and third lines, the host entries, give gpmon access to all Greenplum Database databases.

    Note: It might be necessary to edit the lines in the pg_hba.conf file after running the gpperfmon_install utility to limit the gpmon role’s access to databases or to change the authentication method. After you edit the file, run gpstop -u to reload the file in Greenplum Database.

    • To limit gpmon access to just the gpperfmon database, edit the host entries in thepg_hba.conf file. For the gpmon user change the second field from all to gpperfmon:

      1. local      gpperfmon     gpmon                  md5
      2. host       gpperfmon     gpmon    127.0.0.1/28  md5
      3. host       gpperfmon     gpmon    ::1/128       md5

    • The gpperfmon_install utility assumes the default MD5 authentication method. Greenplum Database can optionally be configured to use the SHA-256 hash algorithm to compute the password hashes saved in the system catalog. This is incompatible with the MD5 authentication method, which expects an MD5 hash or clear text password in the system catalog. Because of this, if you have enabled the SHA-256 hash algorithm in the database, you must edit the pg_hba.conf file after running the gpperfmon_install utility. For the host entries, change the authentication method for the gpmon role from md5 to password:

      1. local      gpperfmon     gpmon                 md5 
      2. host       all           gpmon  127.0.0.1/28   password
      3. host       all           gpmon  ::1/128        password

      The password authentication method submits the user’s clear text password for authentication and should not be used on an untrusted network. See “Protecting Passwords in Greenplum Database” in the Greenplum Database Administrator Guide for more information about configuring password hashing.

  3. Updates the password file (.pgpass). In order to allow the data collection agents to connect as the gpmon role without a password prompt, you must have a password file that has an entry for the gpmon user. The utility adds the following entry to your password file (if the file does not exist, the utility will create it):

    1. *:5432:gpperfmon:gpmon:<gpmon_password>

    If your password file is not located in the default location (~/.pgpass), use the --pgpass option to specify the file location.

  4. Sets the server configuration parameters for Greenplum Command Center. The following parameters must be enabled for the data collection agents to begin collecting data. The utility sets the following parameters in the Greenplum Database postgresql.conf configuration files:

    • gp_enable_gpperfmon=on (in all postgresql.conf files)
    • gpperfmon_port=8888 (in all postgresql.conf files)
    • gp_external_enable_exec=on (in the master postgresql.conf file) Data collection agents can be configured by setting parameters in the gpperfmon.conf configuration file. See Data Collection Agent Configuration for details.

    For information about Greenplum Command Center, see the Greenplum Command Center Documentation.

Options

--enable

In addition to creating the gpperfmon database, performs the additional steps required to enable the data collection agents. When --enable is specified the utility will also create and configure the gpmon superuser account and set the Command Center server configuration parameters in the postgresql.conf files.

--password gpmon_password

Required if --enable is specified. Sets the password of the gpmon superuser. Disallowed if --enable is not specified.

--port gpdb_port

Required. Specifies the connection port of the Greenplum Database master.

--pgpass path_to_file

Optional if --enable is specified. If the password file is not in the default location of ~/.pgpass, specifies the location of the password file.

--verbose

Sets the logging level to verbose.

--help | -h | -?

Displays the online help.

Data Collection Agent Configuration

The $MASTER_DATA_DIRECTORY/gpperfmon/conf/gpperfmon.conf file stores configuration parameters for the data collection agents. For configuration changes to these options to take effect, you must save gpperfmon.conf and then restart Greenplum Database server (gpstop -r).

The gpperfmon.conf file contains the following configuration parameters.

ParameterDescription
log_locationSpecifies a directory location for gpperfmon log files. Default is $MASTER_DATA_DIRECTORY/gpperfmon/logs.
min_query_timeSpecifies the minimum query run time in seconds for statistics collection. All queries that run longer than this value are logged in the queries_history table. For queries with shorter run times, no historical data is collected. Defaults to 20 seconds.

If you know that you want to collect data for all queries, you can set this parameter to a low value. Setting the minimum query run time to zero, however, collects data even for the numerous queries run by Greenplum Command Center, creating a large amount of data that may not be useful.
max_log_sizeThis parameter is not included in gpperfmon.conf, but it may be added to this file.

To prevent the log files from growing to excessive size, you can add the max_log_size parameter to gpperfmon.conf. The value of this parameter is measured in bytes. For example:

max_log_size = 10485760

With this setting, the log files will grow to 10MB before the system rolls over to a new log file.
partition_ageThe number of months that gpperfmon statistics data will be retained. The default value is 0, which means that partitions are never dropped automatically.
quantumSpecifies the time in seconds between updates from data collection agents on all segments. Valid values are 10, 15, 20, 30, and 60. Defaults to 15 seconds.If you prefer a less granular view of performance, or want to collect and analyze minimal amounts of data for system metrics, choose a higher quantum. To collect data more frequently, choose a lower value.
harvest_intervalThe time, in seconds, between data harvests. A data harvest moves recent data from the gpperfmon external (_tail) tables to their corresponding history files. The default is 120. The minimum value is 30.
smdw_aliasesThis parameter allows you to specify additional host names for the standby master. For example, if the standby master has two NICs, you can enter:

smdw_aliases=smdw-1,smdw-2

This optional fault tolerance parameter is useful if the Greenplum Command Center loses connectivity with the standby master. Instead of continuously retrying to connect to host smdw, it will try to connect to the NIC-based aliases of smdw-1 and/or smdw-2. This ensures that the Command Center Console can continuously poll and monitor the standby master.

Notes

The gpperfmon database and Greenplum Command Center require the gpmon role. After the gpperfmon database and gpmon role have been created, you can change the password for the gpmon role and update the information that Greenplum Command Center uses to connect to the gpperfmon database:

  1. Log in to Greenplum Database as a superuser and change the gpmon password with the ALTER ROLE command.

    1. # ALTER ROLE gpmon WITH PASSWORD '<new_password>' ;

  2. Update the password in .pgpass file that is used by Greenplum Command Center. The default file location is the gpadmin home directory (~/.pgpass). The .pgpass file contains a line with the gpmon password.

    1. *:5432:gpperfmon:gpmon:<new_password>

  3. Restart the Greenplum Command Center with the Command Center gpcmdr utility.

    1. $ gpcmdr --restart

The gpperfmon monitoring system requires some initialization after startup. Monitoring information appears after a few minutes have passed, and not immediately after installation and startup of the gpperfmon system.

Examples

Create the gpperfmon database only:

  1. $ su - gpadmin
  2. $ gpperfmon_install --port 5432

Create the gpperfmon database, create the gpmon superuser, and enable the data collection agents:

  1. $ su - gpadmin
  2. $ gpperfmon_install --enable --password changeme --port 5432
  3. $ gpstop -r

See Also

gpstop