May 2018
Intermediate to advanced
576 pages
30h 25m
English
As 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.