RAC & NFS noac mount option under AIX

One of our production databases is a 2 node RAC extended cluster, OS is AIX 7.2
(Oracle 18c that should be migrated to 19c by the end of the year) We are using 3 NFS mounts for :

• reading golden gate trail files (There is a golden gate Replicat running on this database)
• writing RMAN backups
• writing csv files with utl_filesand reading csv files with external tables

• For RMAN the documentation states that we should not be using the noac option, that's ok.
• For Goldengate the documentation states that we should be using the noac option. (Oracle GoldenGate Best Practice: NFS Mount options for use with GoldenGate (Doc ID 1232303.1)).
• I have not found anything related to the NFS mount option in a RAC database for reading and writing csv files using respectively external tables and utl_file.

We have a process that is writing ~2500 csv files, on the old NFS with the noac option is was taking 3 minutes, with the new NFS with the noac option it's now taking more than 30 minutes, on the new NFS without the noac option it's taking 30 seconds.
I have no metrics for the goldengate replication in our testing environment.

Does anyone know if there is a mount option best practice for my third case? Should I consider those csv files as datafiles which means we should use the noac option.

If noac is mandatory, I'll try to convince dba and storage teams to use ACFS instead of NFS. (We are currently using ASM for datafiles)

Best regards,
Thomas Ranchon

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