Siebel Database Upgrade Guide > Preparing an Oracle Database for a Siebel Upgrade >
Setting Oracle Database Configuration Parameters for a Siebel Upgrade
Upgrades from: All Supported Siebel releases.
Environments: Development, production test, production.
Databases: Oracle only.
This topic is part of an upgrade process. See How to Perform a Siebel Database Upgrade.
This topic provides upgrade-specific settings for the Oracle RDBMS. Use the following strategy to set parameters:
Before upgrading an Oracle Database, complete the following tasks:
- Verify that your Oracle clients and Oracle Database server are at the same release level.
- UNIX only. If you have installed the Oracle 64-bit client on the Siebel Server, verify that $ORACLE_HOME/lib32 instead of $ORACLE_HOME/lib is included in LIBPATH (AIX), SHLB_PATH (HP-UX), LD_LIBRARY_PATH (Solaris).
- pctincrease. For upgrades, compute a high enough value for
pctincrease on tablespaces that contain application tables and indexes so that upgrading does not create large numbers of extents.
- pctfree. Rebuild some of your larger tables with a large value for
pctfree (30 or higher). Table size depends on which Siebel applications you have installed. For example, if you are upgrading Siebel Financial Services, S_ASSET is a large table and S_ADDR_ORG is not used at all.
You must increase
pctfree before the upgrade because many new columns are added to tables during the upgrade. Migrating data into the new columns during the upgrade is likely to cause row chaining, which degrades upgrade performance.
- DB_CACHE_SIZE. Set this parameter to a minimum of 394264576.
- SORT_AREA_SIZE. Set this parameter to a minimum of 1524288. This significantly reduces the time required to complete a repository merge.
- Other init.ora parameters that the DBA should review are:
- sort_area_retained size
- UNDO_MANAGEMENT (Oracle 10g and later). Set UNDO_MANAGEMENT = MANUAL before the repository merge. This turns off Automatic Undo Management (AUM). You can turn AUM back on after the repository merge, as desired. For more information on how AUM affects upgrade, see Alert 477025.1 on OracleMetalink 3. This document was previously published as Alert 848.
- Rollback Segments. Verify that you have only one large rollback segment on line that is appropriately sized so that the largest of transactions can be accommodated. Take all other rollback segments off line.
The upgrade may affect some of the largest tables in your implementation of Siebel 7.x, causing them to grow by as much as 40%.
Customer experience has shown that repository merges involving multiple languages can require a rollback segment as large as 1 GB.
Query Optimizer Settings
For the upgrade, use the query optimizer settings listed in Bulletin 478028.1 (Doc ID) OracleMetalink 3.
This document was previously published as Siebel Technical Note 582 and Siebel Alert 1011.