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Setting Oracle Database Configuration Parameters for a Siebel Upgrade


Upgrades from: All 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:

  • Read System Requirements and Supported Platforms on Siebel SupportWeb to determine the supported Oracle version and any required patches. If required, upgrade your Oracle database and client software to the supported version, using Oracle's tools and documented procedures.
  • Set parameters using the recommendations in Technical Note 582 and Alert 1011 on Siebel SupportWeb.
  • Set additional parameters using the recommendations in Siebel Installation Guide for the operating system you are using. Recommendations are located in the chapter on configuring the RDBMS.
  • Configure the database and set parameters as indicated in the following topics.
  • After the upgrade, reset the configuration parameters to the values listed in Siebel Installation Guide for the operating system you are using and in Technical Note 582.

General Configuration

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).
  • Make sure tablespaces have enough free space to accommodate expected growth as estimated in About Siebel Database Growth Estimates.
  • 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.

    Examples of large tables for upgrades from Siebel 6.x are:

    • s_contact
    • s_evt_act
    • s_srv_req
    • s_src
    • s_org_ext
    • s_addr_org
  • 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
    • log_buffers
  • UNDO_MANAGEMENT (Oracle 9i 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 848 on Siebel SupportWeb.
  • 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 Technical Note 582 and Alert 1011 on Siebel SupportWeb.

Siebel Database Upgrade Guide