Configuring parameter settings for the pgactive extension

boolean

–

Logs complete tuple information for the pgactive extension.

boolean

–

Determines whether the pgactive extension logs the detected conflicts to the pgactive.pgactive_conflict_history table. For more information, see Conflict logging for details.

boolean

–

Determines whether the pgactive extension logs the detected conflicts to the PostgreSQL log file. For more information, see Conflict logging for details.

boolean

off

Determines the commit behavior for pgactive apply workers. When disabled(off), apply workers perform asynchronous commits, which improves PostgreSQL throughput during apply operations but delays replay confirmations to the upstream. Setting it to off is always safe and won't cause transaction loss or skipping. This setting only affects the timing of disk flushes on the downstream node and when confirmations are sent upstream. The system delays sending replay flush confirmations until commits are flushed to disk through unrelated operations like checkpoints or periodic work. However, if the upstream has the downstream listed in synchronous_standby_names, setting it to off causes synchronous commits on the upstream to take longer to report success to the client. In this case, set the parameter to on.

string

–

Defines the temporary storage path required for database cloning operations during initial setup. This directory must be writable by the postgres user and have sufficient storage space to contain a complete database dump. The system uses this location only during initial database setup with logical copy operations. This parameter isn't used by the pgactive_init_copy command.

milliseconds

-1

Specifies the maximum wait time for DDL lock before forcibly aborting concurrent write transactions. The default value is -1, which adopts the value set in max_standby_streaming_delay. This parameter accepts time units. For example, you can set it to 10s for 10 seconds. During this wait period, the system attempts to acquire DDL locks while waiting for ongoing write transactions to either commit or roll back. For more information, see the DDL Locking.

milliseconds

-1

Specifies how long a DDL lock attempt waits to obtain the lock. The default value is -1, which uses the value specified in lock_timeout. You can set this parameter using time units such as 10s for 10 seconds. This timer only controls the waiting period for obtaining a DDL lock. Once the system obtains the lock and begins the DDL operation, the timer stops. This parameter doesn't limit the total duration a DDL lock can be held or the overall DDL operation time. To control the total duration of the operation, use statement_timeout instead. For more information, see DDL Locking.

boolean

–

Overrides the default debug log level for DDL locking operations in the pgactive extension. When configured, this setting causes DDL lock-related messages to be emitted at the LOG debug level instead of their default level. Use this parameter to monitor DDL locking activity without enabling the verbose DEBUG1 or DEBUG2 log levels across your entire server.

Available log levels, in increasing order of verbosity:

For more information about monitoring options, see Monitoring global DDL locks.

integer

–

Sets an apply delay (in milliseconds) for configured connections that don't have an explicit apply delay in their pgactive.pgactive_connections entry. This delay is set during node creation or join time, and pgactive won't replay a transaction on peer nodes until at least the specified number of milliseconds have elapsed since it was committed.

Primarily used to simulate high-latency networks in testing environments to make it easier to create conflicts. For example, with a 500ms delay on nodes A and B, you have at least 500ms to perform a conflicting insert on node B after inserting a value on node A.

integer

–

Specifies the duration (in seconds) that a database worker attempts to establish connections during failed attempts. The worker makes one connection attempt per second until it succeeds or reaches this timeout value. This setting is useful when the database engine starts before the worker is ready to establish connections.

boolean

on

Controls how DDL changes are replicated or handled in Amazon RDS with pgactive enabled. When set to on, the node processes DDL changes like a non-pgcctive node. The following requirements apply when working with this parameter:

You can modify this parameter in two ways with super user privileges: globally, locally (session level).

boolean

–

This parameter is for internal use only. When you set this parameter in a transaction, the changes are not replicated to other nodes in your DB cluster.

boolean

–

This parameter is intended for specialist use only. We recommend using this parameter only when troubleshooting specific replication issues. Use this parameter when:

This setting overrides the following error message and allows data divergence to arise to let replication continue: cannot right-pad mismatched attributes; attno %u is missing in local table and remote row has non-null, non-dropped value for this attribute

boolean

–

When set to on, it emits a log message for each remote action that downstream apply workers process. The logs include:

The logs also capture queued DDL commands and table drops.

By default, the logs do not include row field contents. To include row values in the logs, you must recompile with the following flags enabled:

–

You can configure connection parameters for all peer node connections with pgactive nodes. These parameters control settings such as keepalives and SSL modes. By default, pgactive uses the following connection parameters:

To override the default parameters, use the following similar command:

Individual node connection strings take precedence over both these settings and pgactive's built-in connection options. For more information about connection string formats, see libpq connection strings.

We recommend keeping the default keepalive settings enabled. Only disable keepalives if you experience issues with large transactions completing over unreliable networks.

–

Specifies the number of parallel jobs that pg_dump and pg_restore can use during logical node joins with the pgactive.pgactive_join_group function.

Changes to this setting take effect when you reload the configuration. You don't need to restart the server.

int

4

Specifies the maximum number of nodes allowed in a pgactive extension group. The default value is 4 nodes. You must consider the following when setting the value of this parameter:

You can set this parameter in two ways: in the configuration file, using the ALTER SYSTEM SET command

Default value for this parameter is 4, meaning, there can be maximum of 4 nodes allowed in the pgactive extension group at any point of time.

boolean

–

This parameter is intended for internal use only. When enabled, pgactive extension allows creation of pgactive node identifier getter function.