Server Configuration Parameters
The metrics collector extension in Greenplum Database defines custom server configuration parameters to configure metrics collection options. If the metrics collector extension is installed and the value of the
shared_preload_libraries configuration parameter includes
metrics_collector when Greenplum Database starts, these parameters can be viewed and set using the Greenplum Database
on, the metrics collector sends query metrics to the Greenplum Command Center agent.
offthe metrics collector does not collect queries executed by the gpmon user in the gpperfmon database or plan node history for queries that run in less than ten seconds (or
min_query_time, if it is set and greater than 10 seconds). If enabled in a session, the metrics collector collects those queries in the session.
gp_enable_query_metricsis set to on, Greenplum Database allocates space in shared memory to save query metrics. This memory is organized as a header and a list of slots. The number of slots needed depends on the number of concurrent queries and the number of execution plan nodes per query. The default value, 5120, is based on a Greenplum Database system that executes a maximum of about 250 concurrent queries with 120 nodes per query. If the
gp_enable_query_metricsconfiguration parameter is off, or if the slots are exhausted, the metrics are maintained in local memory instead of in shared memory.