I've done quite a lot of Sybase admin, and tweaking the OS to get the better performance for any RDBMS is normal.

As others have mentioned you should at first concentrate on backup/restore procedures, and then on the general system maintenance (such as space usage, index maintenance, etc).

I don't know PostgreSQL, but for Sybase there are a few "standard" operations that you'd need to do, such as full db dumps, transaction dumps (i.e. incremental dumps), index statistics maintenance, database consistency checks, and table reorg operations.

All of these can be easily automated via simple perl (or shell) scripts.

Michael