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UNIX: TNS-12518,TNS-12536 When Listener Load Increases (Doc ID 1920559.1)

Last updated on JUNE 18, 2018

Applies to:

Oracle Net Services - Version to [Release 11.2]
Information in this document applies to any platform.


During heavy load testing, the following errors are reported in the listener log and the connection are rejected:

TNS-12518: TNS:listener could not hand off client connection
TNS-12536: TNS:operation would block
 TNS-12560: TNS:protocol adapter error
  TNS-00506: Operation would block
  Linux Error: 11: Resource temporarily unavailable

The issue can be reproduced at will with the following steps:
1. Run load test

The issue has the following business impact:
Due to this issue, remote client connections are failing and the listener log is throwing errors.


 This is likely a new installation or there has been a significant increase in the number of incoming connections.


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