Hi Stefan,
sorry for challenging your patience but there is again something I don't understand.
We are using AIX 6.1 and Oracle 11.2.0.2. We haven't mounted the filesystem with cio-option.
According to your explanation we shouldn't experience a performance break-down because this new O_CIOR allows to combine the benefits of performant access of Oracle using CIO and other programs can access the same files without performance break-down.
Why do we experience a decreased performance when changing from ASYNCH to SETALL?
Probably I have a Gordian knot in my brain.
Best regards, Henning