One of the early things that I worked on after joining NetApp was to work on this joint performance testing and paper with IBM NFS engineering
Since Netapp storage systems support NFS, iSCSI as well FCP to access to the data, we compared performance on these protocols in a given configuration and this led to work that improved NFS performance for oracle database use.
The paper may be useful to those that are considering deploying Oracle on AIX with NetApp storage and provides various host and storage tuning guidelines as well.
I have repeated similar paper on RHEL4 Linux
Here we endedup improving iSCSI driver in Linux 2.6, as well NFS in Linux 2.6 for Oracle databases.