How to verify if Oracle is using asynchronous I/O?

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux 5

Issue

  • How can we verify at the OS-level whether Oracle is allowed and configured to use asynch I/O?

Resolution

Section 12.5. Verifying Asynchronous I/O Usage of the Tuning and Optimizing Red Hat Enterprise Linux for Oracle 9i and 10g Databases guide explains:

  • Test whether oracle was relinked with asynchronous I/O using ldd or nm. Output similar to the following is desired.

    $ ldd $ORACLE_HOME/bin/oracle | grep libaio
        libaio.so.1 => /usr/lib/libaio.so.1 (0x0093d000)
    $ nm $ORACLE_HOME/bin/oracle | grep io_getevent
        w io_getevents@@LIBAIO_0.1
    
  • Verify whether running Oracle processes are making asynchronous I/O calls by inspecting /proc/slabinfo.

    • See the above link for more detail.

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