PostgreSQL 11 Administration Cookbook

Tablespace-level tuning

Since each tablespace has different I/O characteristics, we may wish to alter the planner cost parameters for each tablespace. These can be set with the following command:

ALTER TABLESPACE new_tablespace SET (seq_page_cost = 0.05, random_page_cost = 0.1);

In this example, settings are roughly appropriate for an SSD drive, and it assumes that the drive is 40 times faster than an HDD for random reads, and 20 times faster for sequential reads.

The values given need more discussion than we have time for here; these are only examples to demonstrate the procedure to change the settings.