Exam 1z0-083 topic 1 question 88 discussion

A is correct Prioritized Tuning Steps: Step 1: Tune the Business Rules Step 2: Tune the Data Design Step 3: Tune the Application Design Step 4: Tune the Logical Structure of the Database Step 5: Tune Database Operations Step 6: Tune the Access Paths Step 7: Tune Memory Allocation Step 8: Tune I/O and Physical Structure Step 9: Tune Resource Contention Step 10: Tune the Underlying Platform(s) https://docs.oracle.com/cd/A87860_01/doc/server.817/a76992/ch2_meth.htm

I find this: https://docs.oracle.com/cd/E11882_01/server.112/e10839/tuning.htm#UNXAR238 Before tuning the database, you must observe its normal behavior by using the tools described in the "Operating System Tools" section. For me the correct answer is C.

Although OS should be checked before Instance Tuning, in my opinion SQL should be tuned before Instance Tuning. Do not ask what you do not need.

what's the first thing you check in an AWR? you can have the best infra but still have performance issues with a poorly designed sql

based on that: https://docs.oracle.com/en/database/oracle/oracle-database/23/tdppt/oracle-database-performance-method.html#GUID-D8F76D20-8E7C-4FF8-9F03-918E94A8E49E Preparing the Database for Tuning 1- Get feedback from users. 2- Check the operating systems of all systems involved with user performance. 3- Ensure that the STATISTICS_LEVEL initialization parameter is set to TYPICAL 4- Ensure that the CONTROL_MANAGEMENT_PACK_ACCESS initialization parameter is set to DIAGNOSTIC+TUNING (default) or DIAGNOSTIC to enable ADDM.

i believe C http://dba-oracle.com/images/sql_tuning_hierarchy.gif

E is the correct answer. instance tunning is always done before performance tunning

A - This answer is based on opinion, How it's possible? But first of all, we need to check the sql statement in my opinion.

How answer based on opinion can be part of oracle exam? I say C

Can be a matter of opinion. My opinion is C - check host / OS health first, to see how the environment may, or may not, be contributing to the issue.

E is correct Instance Tuning Diagnosing and Tuning Database Performance discusses the factors involved in the tuning and optimizing of an Oracle database instance. When considering instance tuning, take care in the initial design of the database to avoid bottlenecks that could lead to performance problems. In addition, you must consider: Allocating memory to database structures Determining I/O requirements of different parts of the database Tuning the operating system for optimal performance of the database After the database instance has been installed and configured, you must monitor the database as it is running to check for performance-related problems. https://docs.oracle.com/en/database/oracle/oracle-database/19/tgdba/performance-tuning-overview.html#GUID-8CA60F1A-5C7A-421C-9DE1-09757F085C3B

OS is a foundation for a DB, then a non-working OS means a non-working database. I think that C is obvious.

A or C& but tuning SQL statements can lead to the normalization of many problems with the OS https://docs.oracle.com/cd/E11882_01/server.112/e10839/tuning.htm#UNXAR008 It is better to choose option A

A is the correct Because Oracle's memory requirements vary depending on your application, you should tune memory allocation after tuning your application and your SQL statements. Allocating memory before tuning your application and your SQL statements may make it necessary to resize some Oracle memory structures to meet the needs of your modified statements and application.

Personally at first I look at the operating system and resource consumption, it's the easiest step leading to easy wins in most cases. However according to best practices looking at this question the correct answer is A.

C Courseware: Check the OS statistics and general machine health before tuning the instance to be sure that the problem is in the database.