Tuning indexes on RAC environments-3

Reversing the index key This is accomplished by executing the following SQL statement: ALTER INDEX <index_name> REBUILD REVERSE; A reverse key index will invert the bytes of the index key column, so that values originally stored in the same block may be spread across multiple index leaf blocks. That will reduce buffer busy contention especially […]

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Tuning indexes on RAC environments-2

Globally busy buffers due to contention for index leaf and branch blocks As we discussed in previous sessions, because of batch INSERT high concurrency could occur for a relatively small set of index leaf and branch blocks, where index keys are populated with monotonically ascending values.The symptoms are increased frequencies and wait times for a […]

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Tuning indexes on RAC environments-1

Introduction and Significance of tuning indexes in RAC environments. Oracle E-Business environment with financial modules like AP and GL having large scale payment invoices transaction. Let me take example of one my public sector clients, they do process of 3 million payment instructions every night. Such most insert intensive applications running on RAC the frequency […]

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Index Performance Tuning Techniques for RAC

It’s been quite some time since my readers are requesting to see some posts on RAC performance tuning concepts and practices. In the process of testing some of the tuning techniques, as well as discussing and interpreting the results, I am preparing a four-day in depth session to understand index performance tuning techniques for RAC. […]

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Oracle Dictionary – DBA Views – Quick Reference

SQL> SELECT * FROM DICT WHERE TABLE_NAME LIKE ‘DBA_%’ ORDER BY TABLE_NAME; TABLE_NAME COMMENTS —————————— —————————————————————————————————- DBA_2PC_NEIGHBORS – information about incoming and outgoing connections for pending transactions DBA_2PC_PENDING – info about distributed transactions awaiting recovery DBA_ADVISOR_ACTIONS – DBA_ADVISOR_COMMANDS – DBA_ADVISOR_DEFINITIONS – DBA_ADVISOR_DEF_PARAMETERS – DBA_ADVISOR_DIRECTIVES – DBA_ADVISOR_FINDINGS – DBA_ADVISOR_JOURNAL – DBA_ADVISOR_LOG – DBA_ADVISOR_OBJECTS – DBA_ADVISOR_OBJECT_TYPES – […]

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New patch required after installing PSU 11.1.0.7.1 to ASM environments

An ASM Regression issue has been reported with 11.1.0.7.1 PSU. A Mandatory patch is being recommended to resolve the ASM regression issue. There is very high possibility of running into the ASM regression issue with 11.1.0.7.1 PSU. No action is required if ASM is not being used in the environment Some of the symptoms are: […]

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Oracle Support – Useful Metalink References

Patch Set Updates for Oracle Products [ID 854428.1] Quick Guide to Avoid Issues in Creating DB Control Using EMCA [ID 750768.1] Interesting links around Autoconfig in the E-Business-Suite [ID 949160.1] Oracle E-Business Suite Recommended Performance Patches [ID 244040.1] CMCLEAN.SQL – Non Destructive Script to Clean Concurrent Manager Tables [ID 134007.1] Cloning Oracle Applications Release 11i […]

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