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Steps to enable event 16421 to Track the Redo Transport Delay (Doc ID 2799775.1)

Last updated on APRIL 17, 2023

Applies to:

Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.


 This article explains steps to enable event 16421 on both primary and standby to track the network activity.

Important Note :

1. It is mandatory to enable tracing on both primary and standby to compare the performance.

2. From 12.2 use alter session to enable trace.

3. Setting event 16421 to level 2 will only enable the code to gather and output the statistical information.

4. This helps to determine what is causing the delay in LGWR, network or standby IO.

5. Compare the Percentage of time in disk layer with Percentage of time in network.

6. Event 16421 is a dynamic tracing doesn't require primary or standby database bounce.

7. No need  to defer and enable REDO transport destination(log_archive_Dest_n)




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In this Document
 For Database version
 For Database versions from 12.2

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