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ORA-27090: Unable to reserve kernel resources for asynchronous disk I/O in 12.1 (Doc ID 2188232.1)

Last updated on AUGUST 24, 2021

Applies to:

Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Information in this document applies to any platform.


Started seeing the below error messages in the parallel secondary processes in batch processing after migrating to 12.1. This was never a problem in earlier versions and used to work fine.

You would also observe the value of "fs.aio-nr" is no where close to the max value of "fs.aio-max-nr" during issue period. The value of "fs.aio-max-nr" is also set to sufficiently high value and more than minimal recommended value of 3145728. 


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