Support Article

Merge into high disk/IO and row contention



When merged into high disk/IO and row contention, user is seeing  sporadic high DB disk i/o, long query execution time, and row lock contention.

​This is most evident in MERGE INTO statements for the primary work table.

Error Messages

Row lock waits are high in Oracle, as well as high reads on LOB tablespaces.

Steps to Reproduce

High overall system usage.

Root Cause

A defect or configuration issue in the operating environment.  

When using Oracle secure files for blob storage with default settings one can see a large number of busy waits related to contention on the blob table.


Follow the steps outlined in this document to improve performance and minimize contention:

Published December 17, 2016 - Updated January 3, 2017

Have a question? Get answers now.

Visit the Collaboration Center to ask questions, engage in discussions, share ideas, and help others.