Many people start their PostgreSQL tuning work by asking about how to spread the various pieces of the database across a large disk array. Recommending how to do that is really application-specific, and it's only after covering so much background the last few chapters that the right context is available to even discuss it.
If you have a really large number of disks available, a dozen or more, presuming that disk space needed for the database wasn't a problem, a good configuration would look like the following:
|
Location |
Disks |
RAID level |
Purpose |
|
/ (root) |
2 |
1 |
OS |
|
$PGDATA |
6+ |
10 |
Database |
|
$PGDATA/pg_wal |
2 |
1 |
WAL |
|
$PGDATA/pg_wal |
2 |
1 |
WAL |
|
Tablespace |
1+ |
None |
