Aurora
RDS
PostgreSQLIntroduction
Since there are significant differences in non-modifiable parameters between AWS Aurora and RDS PostgreSQL and I was getting confused, I noted down the differences. Using the commands below, I extracted parameters where “IsModifiable” is “FALSE”.
Commands
RDS PostgreSQL
aws rds describe-db-cluster-parameters --db-cluster-parameter-group-name default.aurora-postgresql11 | jq -r '["Name","Value","AllowedValues","IsModifiable","Source","ApplyType","DataType","Description","ApplyMethod","MinimumEngineVersion"], (.Parameters[] | [.ParameterName,.ParameterValue,.AllowedValues,.IsModifiable,.Source,.ApplyType,.DataType,.Description,.ApplyMethod,.MinimumEngineVersion]) | @csv'
Aurora PostgreSQL DB Cluster Parameter Group
aws rds describe-db-cluster-parameters --db-cluster-parameter-group-name default.aurora-postgresql11 | jq -r '["Name","Value","AllowedValues","IsModifiable","Source","ApplyType","DataType","Description","ApplyMethod","MinimumEngineVersion"], (.Parameters[] | [.ParameterName,.ParameterValue,.AllowedValues,.IsModifiable,.Source,.ApplyType,.DataType,.Description,.ApplyMethod,.MinimumEngineVersion]) | @csv'
Aurora PostgreSQL DB Parameter Group
aws rds describe-db-parameters --db-parameter-group-name default.aurora-postgresql11 | jq -r '["Name","Value","AllowedValues","IsModifiable","Source","ApplyType","DataType","Description","ApplyMethod","MinimumEngineVersion"], (.Parameters[] | [.ParameterName,.ParameterValue,.AllowedValues,.IsModifiable,.Source,.ApplyType,.DataType,.Description,.ApplyMethod,.MinimumEngineVersion]) | @csv'
List of Non-Modifiable Parameters
Targeting PostgreSQL 11. Lists parameters where “IsModifiable” is “FALSE”.
Note: Even if a parameter appears as modifiable, be careful about how the actual behavior changes. For example, Aurora has different checkpoint behavior from RDS PostgreSQL, so changing full_page_writes may not actually change the behavior.
| RDS | Aurora (DB Cluster Parameter Group) | Aurora (DB Parameter Group) |
|---|---|---|
| archive_command | archive_command | checkpoint_timeout |
| archive_timeout | archive_timeout | config_file |
| config_file | checkpoint_timeout | db_user_namespace |
| data_directory | config_file | effective_io_concurrency |
| db_user_namespace | data_directory | exit_on_error |
| exit_on_error | db_user_namespace | hba_file |
| fsync | effective_io_concurrency | hot_standby_feedback |
| full_page_writes | exit_on_error | ident_file |
| hba_file | hba_file | listen_addresses |
| ident_file | hot_standby_feedback | lo_compat_privileges |
| listen_addresses | huge_pages | log_directory |
| lo_compat_privileges | ident_file | log_file_mode |
| log_directory | listen_addresses | log_line_prefix |
| log_file_mode | lo_compat_privileges | log_timezone |
| logging_collector | log_directory | log_truncate_on_rotation |
| log_line_prefix | log_file_mode | logging_collector |
| log_timezone | logging_collector | rds.superuser_variables |
| log_truncate_on_rotation | log_line_prefix | restart_after_crash |
| port | log_timezone | ssl_ca_file |
| rds.extensions | log_truncate_on_rotation | ssl_cert_file |
| rds.max_tcp_buffers | min_wal_size | ssl_ciphers |
| rds.superuser_variables | port | ssl_key_file |
| restart_after_crash | rds.extensions | stats_temp_directory |
| server_encoding | rds.superuser_variables | superuser_reserved_connections |
| ssl_ca_file | restart_after_crash | syslog_facility |
| ssl_cert_file | server_encoding | unix_socket_directories |
| ssl_ciphers | ssl_ca_file | unix_socket_group |
| ssl_key_file | ssl_cert_file | unix_socket_permissions |
| stats_temp_directory | ssl_ciphers | wal_receiver_status_interval |
| superuser_reserved_connections | ssl_key_file | |
| syslog_facility | stats_temp_directory | |
| unix_socket_directories | superuser_reserved_connections | |
| unix_socket_group | syslog_facility | |
| unix_socket_permissions | unix_socket_directories | |
| wal_sync_method | unix_socket_group | |
| unix_socket_permissions | ||
| wal_receiver_status_interval |