I got ” ORA-27090 Unable to Reserve Kernel Resources Error ” error in Oracle database.
ORA-27090 Unable to Reserve Kernel Resources Error
Details of error are as follows.
ORA-27090: Unable to reserve kernel resources for asynchronous disk I/O Cause: The system call to reserve kernel resources for asynchronous I/O has failed. Action: Check errno
Unable to reserve kernel resources for asynchronous disk I/O
This ORA-27090 is related with the system call to reserve kernel resources for asynchronous I/O has failed.
You discover messages of this nature in your alert log:
Additional information: 3
Additional information: 128
Additional information: 65536
– OR –
Additional information: 3
Additional information: 128
Additional information: 65536
– OR –
Linux-x86_64 Error: 4: Interrupted system call
Additional information: 3
Additional information: 128
Additional information: 65536
Strace against DBWR shows:
which is related to “aio-max-nr” kernel limit.
The “aio-max-nr” kernel limit is too low.
The “aio-max-nr” kernel limit should be adjusted according to Oracle recommendations which are available in this document:
Also, this parameter should be set as follows:
————————————-
fs.aio-max-nr= 3145728
————————————-
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