RE: NFS and direct IO

From: Chitale, Hemant Krishnarao <>
Date: Mon, 18 Apr 2011 11:18:54 +0800
Message-ID: <>

The note still requires forcedirectio on Solaris and HPUX and cio on AIX even for non-RAC implementations.

It's not clear to me if the NFS implementation is on Linux or on a Unix flavour, because you say " The NFS database is using direct-IO so there is no longer the buffering from the UNIX."

Hemant K Chitale

-----Original Message-----
From: D'Hooge Freek [] Sent: Sunday, April 17, 2011 1:46 AM
Subject: RE: NFS and direct IO


Directio is only required on linux when working with rac. See note Mount Options for Oracle files when used with NAS devices [ID 359515.1]


Freek D'Hooge
Oracle Database Administrator
tel +32(0)3 451 23 82

From: [] On Behalf Of kyle Hailey Sent: zaterdag 16 april 2011 18:31
Subject: NFS and direct IO

Is there any requirement to use direct I/O with NFS? (besides performance)

from metalink note: Enterprise Linux: Linux, Filesystem & I/O Type Supportability [ID 279069.1]

    DIRECTIO is required for database files on NAS (network attached storage).

Is it really  required? I can't find any other reference that supports this.


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Received on Sun Apr 17 2011 - 22:18:54 CDT

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