Veritas Storage Foundation™ for Oracle 5.0.1 Administrator's Guide

■ You must have permission to change file system behavior using
the vxtunefs command to enable or disable Cached Quick I/O.
By default, you need superuser (root) permissions to run the
vxtunefs command, but other system users do not. Superuser
(root) must specifically grant database administrators permission
to use this command as follows:
# chown root:dba /sbin/fs/vxfs5.0/vxtunefs
# chmod 4550 /sbin/fs/vxfs5.0/vxtunefs
where users belonging to the dba group are granted permission
to run the vxtunefs command. We recommend this selective,
more secure approach for granting access to powerful commands.
■ You must enable Quick I/O on the file system. Quick I/O is enabled
automatically at file system mount time.
If you have correctly enabled Quick I/O on your system, you can
proceed to enable Cached Quick I/O as follows:
■ Set the file system Cached Quick I/O flag, which enables Cached
Quick I/O for all files in the file system.
■ Setting the file system Cached Quick I/O flag enables caching for
all files in the file system. You must disable Cached Quick I/O on
individual Quick I/O files that do not benefit from caching to avoid
consuming memory unnecessarily. This final task occurs at the
end of the enabling process.
Prerequisites
■ Do not enable Cached Quick I/O if Oracle is using Oracle Disk
Manager.
Usage notes
Enabling and disabling the qio_cache_enable flag
As superuser (root), set the qio_cache_enable flag using the vxtunefs command
after you mount the file system.
Using Veritas Cached Quick I/O
Enabling Cached Quick I/O on a file system
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