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Tag: 11g

  • OBIEE Performance Tuning Part 3

    For the final part of this guide we will take a look at some of the changes that can be made to the database to achieve better performance. The parameters I recommend changing are listed below;

     

    
db_block_checksum – TRUE - database writer process will calculate a checksum

db_file_multiblock_read_count – 0

dml_locks - 1000 - minimize lock conversions and achieve better query / Read performance.

job_queue_processes - 2 - This limits the total number of dbms_scheduler and dbms_job jobs that can be running at a given time. Thus, saving database resources

log_buffer - 10485760 - larger values for log_buffer will reduce redo log file I/O.

log_checkpoint_interval – 100000

log_checkpoint_timeout – 3600
Open_cursors - 1000
undo_retention - 90000
Database resource plan – Internal/off

    Implementing these changes reduced my report timings further showing a clear increase in performance.

    Results:
    Time after changing instanceconfig.xml against Database changes
    1. 1m44s      43s
    2. 2m56s      1m34s
    3. 5m15s      3m19s
    4. 2m42s      1m5s

    This concludes my 3 step guide for OBIEE performance tuning, In future I might write a piece on tuning reports for performance, as the above results we are still above the 1min mark in some reports making sure you write efficient SQL queries by using indexes, partioning and materialized views during development will ensure you are able to reduce these times further.

    Until next time.

  • OBIEE Performance Tuning Part 1

    This is part one of my OBIEE Tuning guide. In this post we will look at some of the parameters that should be set at NQSConfig.ini in order to achieve maximum performance  First things first to run a valid test I ran the same report each time, after I had applied changes rebooted all database and OBIEE services to find time of completion I used the manage sessions section on the Analytics Console (Administration > Manage Sessions). With regards to what is a good and bad result if its not 10 seconds or more faster then I would say the change hasn’t had an effect on performance.

    Note that all SQL should be tuned and it is said that OBIEE should be able to return a report within 1-10 seconds. My instance is not at this stage but you can still see a clear performance increase.

    With my performance testing cache has been turned off as this will give invalid results, when performace tweaking caching should only be turned in the final stage.

    Below changes were made to the NQSConfig.ini

    
MAX_SESSION_LIMIT = 5000
MAX_REQUEST_PER_SESSION_LIMIT = 5000
SERVER_THREAD_RANGE = 40-260
DB_GATEWAY_THREAD_RANGE = 40-520
INIT_BLOCK_CACHE_ENTRIES = 5000 # default is 20

    The settings were saved, database and all BI services restarted.

    The Report I was running contained 4 dashboards they will be listed as 1-4 below.

    Original Report Timings                                                  Changes to NQSConfig.ini Timings
    1.                  2m10s                                                                                                    1m54s
    2.                  3m5s                                                                                                      2m46s
    3.                  5m16s                                                                                                    5m13s
    4.                  2m41s                                                                                                    2m34s

    As you can see from the above there have been slight improvments in the report but one dashboard still runs in pretty much the same time.

    My next post will be on changes made to instanceconfig.xml then finally the changes I made to the database.