tkprof is one of the most useful utilities available to Admins for diagnosing performance issues. It essentially formats a trace file into a more readable format for performance analysis. The DBA can then identify and resolve performance issues such as poor SQL, indexing, and wait events.
Why, When tkprof?
In a nutshell a database index is an auxiliary data structure which allows for faster retrieval of data stored in the database. They are keyed off of a specific column so that queries like “Give me all people with a last name of ‘Sam’” are fast.
In order to avoid trouble arising from corrupted siebns.dat files, we should create backup copies regularly and before each major modification of the Enterprise configuration.
The following command at the srvrmgr prompt allows us to create a backup copy of siebns.dat and specify a name for the new file. If the name is omitted, the file name will contain the current timestamp.
backup nameserver [filename]
Use DB2 load replace option when loading EIM tables and turn off table logging if possible.Use separate tablespaces for EIM tables and the base tables.Use larg
Prior to running EIM it is important to clean up fragmented objects, especially those that will be used during the EIM processing. The following SQL statement can be used to identify objects with greater than 10 extents:
SELECT segment_name,segment_type,tablespace_name,extents
FROM dba_segments
WHERE owner = (Siebel table_owner)
and extents > 9;
Multiple EIM processes can be executed against an EIM table provided they all use different batches or batch ranges. The concern is that contention for locks on common objects may be experienced. To run multiple jobs in parallel against the same EIM table, check that the ‘FREELIST’ parameter is set appropriately for the tables and indexes used in the EIM processing. This would include the EIM tables and indexes as well as the base tables and indexes.
As with most client-server applications, the overall performance of Siebel eBusiness applications is largely dependent on the I/O performance on the database server. To ensure optimal I/O performance, it is critical that the tables and indexes in the database be arranged across available disk devices in a manner that evenly distributes the I/O load.