How to Enable AIX IOCP

Some software like Oracle clusterware (grid) and database require that I/O completion ports (IOCP) to be enabled to handle multiple asynchronous I/O requests in a program and can improve overall system performance.

Check whether I/O completion ports is enabled or not.

> lsdev -Cc iocp
iocp0 Defined  I/O Completion Ports

We have 2 ways to enable it.

Solution 1. Chdev

> mkdev -l iocp0
> chdev -l iocp0 -P -a autoconfig='available'

Solution 2. Smitty

It's a text-based user interface to change the status.

> smitty iocp

Press ENTER to enter first option "Change / Show Characteristics of I/O Completion Ports."

Press TAB to switch value [entry fields] from defined to available

then Press ENTER commit change, and reboot system to take it effect.