Command Center Configuration File Reference

Configuration File Reference

Configuration parameters for Greenplum Command Center are stored in these files:

1. $MASTER_DATA_DIRECTORY/gpperfmon/conf/gpperfmon.conf 

Stores configuration parameters for the Greenplum Command Center agents.

2. $GPPERFMONHOME/instances/instance_name/conf/gpperfmonui.conf and lighttpd.conf 

Stores configuration parameters for the Command Center web application and web server.

3. $MASTER_DATA_DIRECTORY/postgresql.conf

Stores configuration parameters to enable the Greenplum Command Center feature for Greenplum Database server.

Any system user with write permissions to these directories can edit these configuration files.

Command Center Agent Parameters

The $MASTER_DATA_DIRECTORY/gpperfmon/conf/gpperfmon.conf stores configuration parameters for the Command Center agents. 

For configuration changes to these options to take effect, you must save gpperfmon.conf and then restart Greenplum Database server (gpstop -r).

To enable the Command Center agents within Greenplum Database server, you must also set the “Greenplum Database Server Configuration Parameters” .

quantum

Specifies the time in seconds between updates from Command Center 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.

min_query_time

Specifies the minimum query run time in seconds for statistics collection. Command Center logs all queries that run longer than this value 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 Command Center itself, creating a large amount of data that may not be useful.

min_detailed_query_time

Specifies the minimum iterator run time in seconds for statistics collection. Command Center logs all iterators that run longer than this value in the

iterators_history table. For iterators with shorter run times, no data is collected. Minimum value is 10 seconds.

This parameter’s value must always be equal to, or greater than, the value of min_query_time. Setting min_detailed_query_time higher than min_query_time allows you to log detailed query plan iterator data only for especially complex, long-running queries, while still logging basic query data for shorter queries.

Given the complexity and size of iterator data, you may want to adjust this parameter according to the size of data collected. If the iterators_* tables are growing to excessive size without providing useful information, you can raise the value of this parameter to log iterator detail for fewer queries.

log_location

Specifies a directory location for Command Center log files. Default is $MASTER_DATA_DIRECTORY/gpperfmon/logs.

max_log_size

This parameter is not included in gpperfmon.conf, but it may be added to this file for use with Greenplum Command Center. 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.

smdw_aliases

This 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.

Note: These parameters only applies to the Greenplum Data Computing Appliance platform.

Command Center Console Parameters

Each instance of the Command Center Console has two configuration files located in $GPPERFMONHOME/instances/instance_name/conf. The web application file is gpperfmonui.conf and the web server file is lighttpd.conf. After editing these files, reload the configuration by restarting the Command Center Console instance (gpperfmon --restart "instance_name").

Web Application Parameters (gpperfmonui.conf)

allow_trust_logon

Determines whether to allow access to the Greenplum Command Center Console for any user listed in pg_hba.conf using the trust authentication method. When set to yes, trusted Greenplum users are allowed to login to the Command Center console without a password. By default, this parameter is commented out.

server_name

Specifies the instance name displayed on the login page of the Greenplum Command Center Console. This value can be any name you want to display to users,

expressed as a text string. Defaults to the instance name you specified when setting up the Command Center Console.

master_port

Specifies the port number of the Greenplum Database master that this instance is monitoring.

Web Server Parameters (lighttpd.conf)

This file has several configuration parameters, however these are the parameters most likely to change for a Command Center Console installation. For more information on the other parameters in this configuration file, see the lighttpd documentation.

server.port

Sets the web server port number. The default HTTP port is 28080.

ssl.engine

Determines whether SSL encryption is used for client connections. Valid values are enable and disable. If you enable SSL at installation time, this is set to enable.

ssl.pemfile

Specifies the path to the PEM file for SSL support. If you enable SSL at installation time, this parameter points to a self-signed certificate. If you use a trusted signed certificate, you must specify it with this parameter.

Greenplum Database Server Configuration Parameters

The following parameters must be uncommented and set in the server configuration file (postgresql.conf) in order to enable the Command Center data collection agents. gp_enable_gpperfmon and gpperfmon_port must be set in both the master and segment postgresql.conf files. gp_enable_gpperfmon and gp_enable_gpperfmon only need to be set in the master postgresql.conf file.

After changing these settings, the Greenplum Database instance must be restarted for the changes to take effect.

gp_enable_gpperfmon

Turns on the Command Center data collection agent for a segment. Must be set in all

postgresql.conf files (master and all segments).

gpperfmon_port

The default port for the Command Center agents is 8888, but you can set this

parameter to a different port if required (master and all segments).

gp_gpperfmon_send_interval

Sets the frequency in seconds that the Greenplum Database server processes send query execution updates to the Command Center agent processes.

gp_external_enable_exec

This parameter is enabled by default and must remain enabled. It allows the use of external tables that execute OS commands or scripts on the segment hosts. The

Command Center agents use this type of external tables to collect current system metrics from the segments.