Multi-node configuration

Each of these settings can be configured in the postgresql.conf file on the individual node. The postgresql.conf file is usually in the data directory, but you can locate the correct path by connecting to the node with psql and giving this command:

After you have modified the postgresql.conf file, reload the configuration to see your changes:

enable_partitionwise_aggregate

On the access node, set the enable_partitionwise_aggregate parameter to on. This ensures that queries are pushed down to the data nodes, and improves query performance.

On the access node, set jit to . Currently, JIT does not work well with distributed queries. However, you can enable JIT on the data nodes succssfully.

statement_timeout

On the data nodes, set the wal_level to logical or higher to move or chunks between data nodes. If you are moving many chunks in parallel, consider increasing max_wal_senders and max_replication_slots as well.

Transaction isolation level

For consistency, if the transaction isolation level is set to READ COMMITTED it is automatically upgraded to REPEATABLE READ whenever a distributed operation occurs. If the isolation level is , it is not changed.