Carlos Villalba

Oracle 10g Architecture Diagram by IBM

It has been my contention for years that the better the Oracle DBA understands the architecture of the database, the bettter prepared he or she will be to administer the database.
Another point worth mentioning is the knowledge of the Os. When troubleshooting any problem or malfuction in the database it makes a difference early on during the troubleshooting process to determine if the Os s the root cause of the malfunction.

Take the time to learn both the DB architectore and the inner details of that Os as well. Here is a video that does a good job explaining the basis of the Oracle architecture.