Parameter Categories

Parameter Categories

System Resource Consumption Parameters

These parameters set the limits for system resources consumed by Greenplum Database.

Cost-Based Vacuum Delay Parameters

Warning: Do not use cost-based vacuum delay because it runs asynchronously among the segment instances. The vacuum cost limit and delay is invoked at the segment level without taking into account the state of the entire Greenplum Database array

You can configure the execution cost of VACUUM and ANALYZE commands to reduce the I/O impact on concurrent database activity. When the accumulated cost of I/O operations reaches the limit, the process performing the operation sleeps for a while, Then resets the counter and continues execution

vacuum_cost_delay

vacuum_cost_limit

vacuum_cost_page_dirty

vacuum_cost_page_hit

vacuum_cost_page_miss

Transaction ID Management Parameters

Query Tuning Parameters

These parameters control aspects of SQL query processing such as query operators and operator settings and statistics sampling.

Postgres Planner Control Parameters

Postgres Planner Costing Parameters

Warning: Do not adjust these query costing parameters. They are tuned to reflect Greenplum Database hardware configurations and typical workloads. All of these parameters are related. Changing one without changing the others can have adverse affects on performance.

cpu_index_tuple_cost

cpu_operator_cost

cpu_tuple_cost

cursor_tuple_fraction

effective_cache_size

gp_motion_cost_per_row

gp_segments_for_planner

random_page_cost

seq_page_cost

Database Statistics Sampling Parameters

These parameters adjust the amount of data sampled by an ANALYZE operation. Adjusting these parameters affects statistics collection system-wide. You can configure statistics collection on particular tables and columns by using the ALTER TABLESET STATISTICS clause.

default_statistics_target

Sort Operator Configuration Parameters

Query Plan Execution

Control the query plan execution.

gp_max_slices

System Monitoring Parameters

These configuration parameters control Greenplum Database data collection and notifications related to database monitoring.

Greenplum Performance Database

The following parameters configure the data collection agents that populate the gpperfmon database.

gp_enable_gpperfmon

gp_gpperfmon_send_interval

gpperfmon_log_alert_level

gpperfmon_port

Query Metrics Collection Parameters

These parameters enable and configure query metrics collection. When enabled, Greenplum Database saves metrics to shared memory during query execution. These metrics are used by Pivotal Greenplum Command Center, which is included with Pivotal's commercial version of Greenplum Database.

gp_enable_query_metrics

gp_instrument_shmem_size

Runtime Statistics Collection Parameters

These parameters control the server statistics collection feature. When statistics collection is enabled, you can access the statistics data using the pg_stat family of system catalog views.

stats_queue_level

update_process_title

Automatic Statistics Collection Parameters

When automatic statistics collection is enabled, you can run ANALYZE automatically in the same transaction as an INSERT, UPDATE, DELETE, COPY or CREATE TABLE...AS SELECT statement when a certain threshold of rows is affected (on_change), or when a newly generated table has no statistics (on_no_stats). To enable this feature, set the following server configuration parameters in your Greenplum Database master postgresql.conf file and restart Greenplum Database:

gp_autostats_mode

gp_autostats_mode_in_functions

gp_autostats_on_change_threshold

log_autostats

Warning: Depending on the specific nature of your database operations, automatic statistics collection can have a negative performance impact. Carefully evaluate whether the default setting of on_no_stats is appropriate for your system.

Lock Management Parameters

Database Table Parameters

Append-Optimized Table Parameters

The following parameters configure the append-optimized tables feature of Greenplum Database.

max_appendonly_tables

gp_appendonly_compaction

gp_appendonly_compaction_threshold

validate_previous_free_tid

Past Version Compatibility Parameters

The following parameters provide compatibility with older PostgreSQL and Greenplum Database versions. You do not need to change these parameters in Greenplum Database.

Greenplum Database

Greenplum Database Array Configuration Parameters

The parameters in this topic control the configuration of the Greenplum Database array and its components: segments, master, distributed transaction manager, master mirror, and interconnect.

Interconnect Configuration Parameters

Distributed Transaction Management Parameters

Greenplum Mirroring Parameters for Master and Segments

These parameters control the configuration of the replication between Greenplum Database primary master and standby master.

keep_wal_segments

repl_catchup_within_range

replication_timeout

wal_receiver_status_interval

Greenplum PL/Java Parameters

The parameters in this topic control the configuration of the Greenplum Database PL/Java language.

pljava_classpath

pljava_classpath_insecure

pljava_statement_cache_size

pljava_release_lingering_savepoints

pljava_vmoptions

XML Data Parameters

The parameters in this topic control the configuration of the Greenplum Database XML data type.

xmlbinary

xmloption