This page lists the database flags that AlloyDB supports.
You use database flags for many operations, including adjusting PostgreSQL parameters, adjusting options, and configuring and tuning instances.
In some cases, setting one flag may require that you set another flag to fully enable the desired functionality.
When you set, remove, or modify a flag for an instance, the instance might be restarted. The flag value is then persisted for the instance until you remove it.
Flags not mentioned below are not supported.
A | C | D | E | F | G | H | I | J | L | M | O | P | R | S | T | V | W
AlloyDB Flag | Type Acceptable Values and Notes |
Restart Required? |
---|---|---|
alloydb.enable_auto_explain | boolean on | off |
Yes |
alloydb.enable_pg_bigm | boolean on | off |
Yes |
alloydb.enable_pg_cron | boolean on | off |
Yes |
alloydb.enable_pg_hint_plan | boolean on | off |
Yes |
alloydb.enable_pgaudit | boolean on | off |
Yes |
alloydb.enable_pglogical | boolean on | off |
Yes |
alloydb.logical_decoding | boolean on | off |
Yes |
alloydb.pg_shadow_select_role | string |
No |
auto_explain.log_analyze | boolean on | off |
No |
auto_explain.log_buffers | boolean on | off |
No |
auto_explain.log_format | enumeration text | xml | json | yaml |
No |
auto_explain.log_level | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | debug | info | notice | warning | log |
No |
auto_explain.log_min_duration | integer -1 ... 2147483647 |
No |
auto_explain.log_nested_statements | boolean on | off |
No |
auto_explain.log_settings | boolean on | off |
No |
auto_explain.log_timing | boolean on | off |
No |
auto_explain.log_triggers | boolean on | off |
No |
auto_explain.log_verbose | boolean on | off |
No |
auto_explain.log_wal | boolean on | off |
No |
auto_explain.sample_rate | float 0 ... 1 |
No |
autovacuum | boolean on | off |
No |
autovacuum_analyze_scale_factor | float 0 ... 100 |
No |
autovacuum_analyze_threshold | integer 0 ... 2147483647 |
No |
autovacuum_freeze_max_age | integer 100000 ... 2000000000 |
Yes |
autovacuum_max_workers | integer 1 ... 262143 |
Yes |
autovacuum_multixact_freeze_max_age | integer 10000 ... 2000000000 |
Yes |
autovacuum_naptime | integer 1 ... 2147483 |
No |
autovacuum_vacuum_cost_delay | integer -1 ... 100 |
No |
autovacuum_vacuum_cost_limit | integer -1 ... 10000 |
No |
autovacuum_vacuum_scale_factor | float 0 ... 100 |
No |
autovacuum_vacuum_threshold | integer 0 ... 2147483647 |
No |
autovacuum_work_mem | integer -1 ... 2147483647 Unit is kB . |
No |
checkpoint_completion_target | float 0 ... 1 |
No |
checkpoint_timeout | integer 30 ... 86400 Unit is s . |
No |
checkpoint_warning | integer 0 ... 2147483647 Unit is s . |
No |
commit_delay | integer 0 ... 100000 |
No |
commit_siblings | integer 0 ... 1000 |
No |
constraint_exclusion | enumeration partition | on | off |
No |
cpu_index_tuple_cost | float 0 ... 3.4028235e+38 |
No |
cpu_operator_cost | float 0 ... 3.4028235e+38 |
No |
cpu_tuple_cost | float 0 ... 3.4028235e+38 |
No |
cron.database_name | string |
Yes |
cron.log_min_messages | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | debug | info | notice | warning | error | log | fatal | panic |
No |
cron.log_run | boolean on | off |
Yes |
cron.log_statement | boolean on | off |
Yes |
cron.max_running_jobs | integer 0 |
Yes |
cursor_tuple_fraction | float 0 ... 1 |
No |
deadlock_timeout | integer 1 ... 2147483647 Unit is ms . |
No |
default_statistics_target | integer 1 ... 10000 |
No |
default_tablespace | string |
No |
default_transaction_deferrable | boolean on | off |
No |
default_transaction_isolation | enumeration serializable | 'repeatable read' | 'read committed' | 'read uncommitted' Single quotes are required around enumeration strings that contain spaces. |
No |
effective_cache_size | integer 1 ... 2147483647 Unit is blocks. |
No |
enable_bitmapscan | boolean on | off |
No |
enable_hashagg | boolean on | off |
No |
enable_hashjoin | boolean on | off |
No |
enable_indexonlyscan | boolean on | off |
No |
enable_indexscan | boolean on | off |
No |
enable_material | boolean on | off |
No |
enable_mergejoin | boolean on | off |
No |
enable_nestloop | boolean on | off |
No |
enable_seqscan | boolean on | off |
No |
enable_sort | boolean on | off |
No |
enable_tidscan | boolean on | off |
No |
force_parallel_mode | enumeration off | on | regress |
No |
from_collapse_limit | integer 1 ... 2147483647 |
No |
geqo | boolean on | off |
No |
geqo_effort | integer 1 ... 10 |
No |
geqo_generations | integer 0 ... 2147483647 |
No |
geqo_pool_size | integer 0 ... 2147483647 |
No |
geqo_seed | float 0 ... 1 |
No |
geqo_selection_bias | float 1.5 ... 2 |
No |
geqo_threshold | integer 2 ... 2147483647 |
No |
gin_fuzzy_search_limit | integer 0 ... 2147483647 |
No |
gin_pending_list_limit | integer 64 ... 2147483647 Unit is kB . |
No |
google_columnar_engine.column_set_stat_statements_max_memory_size | integer 1048576 ... 2147483647 |
Yes |
google_columnar_engine.memory_size_in_mb | integer 128 ... 2147483647 |
Yes |
google_columnar_engine.enable_columnar_recommendation | boolean on | off |
No |
google_columnar_engine.enable_columnar_scan | boolean on | off |
No |
google_columnar_engine.enabled | boolean on | off |
Yes |
google_columnar_engine.estimate_relation_size_sampling_percentage | float 0.0 ... 100.0 |
No |
google_columnar_engine.hypothetical_config_max_memory_size | integer 1048576 ... 2147483647 |
Yes |
google_columnar_engine.maintenance_cpu_percentage | integer 0 ... 100 |
No |
google_columnar_engine.max_num_pending_whatif_analysis | integer 1 ... 2147483647 |
Yes |
google_columnar_engine.max_parallel_workers_per_job | integer 0 ... 262143 |
No |
google_columnar_engine.max_sampled_query_length | integer 1 ... 2147483647 |
Yes |
google_columnar_engine.query_sampling_percentage | float 0 ... 100 |
No |
google_columnar_engine.refresh_threshold_percentage | integer -1 ... 100 |
No |
google_columnar_engine.refresh_threshold_scan_count | integer 0 ... 2147483647 |
No |
google_columnar_engine.relations | string |
No |
google_columnar_engine.scan_mode | integer 0 ... 2 |
No |
hot_standby_feedback | boolean on | off |
No |
idle_in_transaction_session_timeout | integer 0 ... 2147483647 Unit is ms . |
No |
join_collapse_limit | integer 1 ... 2147483647 |
No |
lock_timeout | integer 0 ... 2147483647 Unit is ms . |
No |
log_autovacuum_min_duration | integer -1 ... 2147483647 |
No |
log_checkpoints | boolean on | off |
No |
log_connections | boolean on | off |
No |
log_disconnections | boolean on | off |
No |
log_duration | boolean on | off |
No |
log_error_verbosity | enumeration terse | default | verbose |
No |
log_executor_stats | boolean on | off |
No |
log_hostname | boolean on | off |
No |
log_lock_waits | boolean on | off |
No |
log_min_duration_statement | integer -1 ... 2147483647 Unit is ms . |
No |
log_min_error_statement | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | info | notice | warning | error | log | fatal | panic |
No |
log_min_messages | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | info | notice | warning | error | log | fatal | panic |
No |
log_parser_stats | boolean on | off |
No |
log_planner_stats | boolean on | off |
No |
log_replication_commands | boolean on | off |
No |
log_statement | enumeration none | ddl | mod | all |
No |
log_statement_stats | boolean on | off |
No |
log_temp_files | integer -1 ... 2147483647 Unit is kB . |
No |
maintenance_work_mem | integer 1024 ... 2147483647 Unit is kB . |
No |
max_connections | integer 1000 ... 240000 This flag's value on a read pool instance must be greater than or equal to the value on the primary instance. Also, the minimum provides at most 970 non-superuser connections, as the superuser_reserved_connections flag reserves 30 connections. |
Yes |
max_locks_per_transaction | integer 10 ... 2147483647 This flag's value on a read pool instance must be greater than or equal to the value on the primary instance. |
Yes |
max_logical_replication_workers | integer 4 ... 8192 Maxiumum value is dependent on instance memory and limited to max_worker_processes . |
Yes |
max_parallel_workers | integer 0 ... 1024 Maximum value is dependent on instance memory. |
No |
max_parallel_workers_per_gather | integer 0 ... 1024 Maximum value is dependent on instance memory. |
No |
max_pred_locks_per_page | integer 0 ... 2147483647 |
Yes |
max_pred_locks_per_relation | integer -2147483648 ... 2147483647 |
Yes |
max_pred_locks_per_transaction | integer 10 ... 1048576 |
Yes |
max_prepared_transactions | integer 0 ... 262143 This flag's value on a read pool instance must be greater than or equal to the value on the primary instance. |
Yes |
max_replication_slots | integer 10 ... 8192 Maximum value is dependent on instance memory. |
Yes |
max_standby_archive_delay | integer -1 ... 2147483647 Unit is ms . |
No |
max_standby_streaming_delay | integer -1 ... 2147483647 Unit is ms . |
No |
max_sync_workers_per_subscription | integer 2 ... 64 Limited by max_logical_replication_workers . |
No |
max_wal_senders | integer 10 ... 8192 This flag's value on a read pool instance must be greater than or equal to the value on the primary instance. Also, maximum value is dependent on instance memory. |
Yes |
max_wal_size | integer 32 ... 2147483647 Unit is MB . Must be at least twice wal_segment_size . |
No |
max_worker_processes | integer 8 ... 4096 This flag's value on a read pool instance must be greater than or equal to the value on the primary instance. Also, maximum value is dependent on instance memory. |
Yes |
min_parallel_relation_size | integer 0 ... 715827882 Unit is 8kB . |
No |
min_wal_size | integer 32 ... 2147483647 Unit is MB . Must be at least twice wal_segment_size . |
No |
old_snapshot_threshold | integer -1 ... 86400 Unit is min . |
Yes |
parallel_setup_cost | float 0 ... 3.4028235e+38 |
No |
parallel_tuple_cost | float 0 ... 3.4028235e+38 |
No |
password_encryption | enumeration md5 | scram-sha-256 |
No |
pg_bigm.enable_recheck | boolean on | off |
No |
pg_bigm.gin_key_limit | integer 0 ... 2147483647 |
No |
pg_bigm.similarity_limit | float 0 ... 1 |
No |
pg_hint_plan.debug_print | enumeration off | on | detailed | verbose | 0 | 1 | 2 | 3 | no | yes | false | true |
No |
pg_hint_plan.enable_hint | boolean on | off |
No |
pg_hint_plan.enable_hint_table | boolean on | off |
No |
pg_hint_plan.message_level | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | debug | info | notice | warning | error | log |
No |
pg_hint_plan.parse_messages | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | debug | info | notice | warning | error | log |
No |
pg_stat_statements.max | integer 100 ... 2147483647 |
Yes |
pg_stat_statements.save | boolean on | off |
No |
pg_stat_statements.track | enumeration none | top | all |
No |
pg_stat_statements.track_utility | boolean on | off |
No |
pgaudit.log | enumeration read | write | function | role | ddl | misc | misc_set | all | none | -read | -write | -function | -role | -ddl | -misc | -misc_set | -all | -none |
No |
pgaudit.log_catalog | boolean on | off |
No |
pgaudit.log_client | boolean on | off |
No |
pgaudit.log_level | enumeration debug | debug5 | debug4 | debug3 | debug2 | debug1 | info | notice | warning | log |
No |
pgaudit.log_parameter | boolean on | off |
No |
pgaudit.log_relation | boolean on | off |
No |
pgaudit.log_statement_once | boolean on | off |
No |
pgaudit.role | string |
No |
pglogical.batch_inserts | boolean on | off |
Yes |
pglogical.conflict_log_level | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | info | notice | warning | error | log | fatal | panic |
No |
pglogical.conflict_resolution | enumeration error | apply_remote | keep_local | last_update_wins | first_update_wins |
No |
pglogical.extra_connection_options | string |
No |
pglogical.synchronous_commit | boolean on | off |
Yes |
pglogical.use_spi | boolean on | off |
Yes |
random_page_cost | float 0 ... 3.4028235e+38 |
No |
replacement_sort_tuples | integer 0 ... 2147483647 |
No |
shared_buffers | integer 16 ... 1073741823 Unit is blocks. |
Yes |
ssl_max_protocol_version | enumeration TLSv1 | TLSv1.1 | TLSv1.2 | TLSv1.3 |
No |
ssl_min_protocol_version | enumeration TLSv1 | TLSv1.1 | TLSv1.2 | TLSv1.3 |
No |
standard_conforming_strings | boolean on | off |
No |
statement_timeout | integer 0 ... 2147483647 Unit is ms . |
No |
synchronize_seqscans | boolean on | off |
No |
tcp_keepalives_count | integer 0 ... 2147483647 |
No |
tcp_keepalives_idle | integer 0 ... 2147483647 |
No |
tcp_keepalives_interval | integer 0 ... 2147483647 |
No |
temp_buffers | integer 100 ... 1073741823 Unit is 8kB . |
No |
temp_file_limit | integer 1048576 ... 2147483647 Unit is kB . |
No |
trace_notify | boolean on | off |
No |
trace_recovery_messages | enumeration debug5 | debug4 | debug3 | debug2 | debug1 | log | notice | warning | error |
No |
trace_sort | boolean on | off |
No |
track_activities | boolean on | off |
No |
track_activity_query_size | integer 100 ... 102400 |
Yes |
track_commit_timestamp | boolean on | off |
Yes |
track_counts | boolean on | off |
No |
track_functions | enumeration none | pl | all |
No |
track_io_timing | boolean on | off |
No |
vacuum_cost_delay | integer 0 ... 100 Unit is ms . |
No |
vacuum_cost_limit | integer 1 ... 10000 |
No |
vacuum_freeze_min_age | integer 0 ... 1000000000 |
No |
vacuum_freeze_table_age | integer 0 ... 2000000000 |
No |
vacuum_multixact_freeze_min_age | integer 0 ... 1000000000 |
No |
vacuum_multixact_freeze_table_age | integer 0 ... 2000000000 |
No |
wal_buffers | integer -1 ... 262143 Unit is blocks. |
Yes |
work_mem | integer 64 ... 2147483647 Unit is kB . |
No |