VERITAS Storage Foundation 4.1 Oracle Administrator's Guide

Understanding Quick I/O Prerelease 8 September 2005, 8:54am
86 VERITAS Storage Foundation for Oracle Administrator’s Guide
Whenever an application opens an existing VxFS file with the extension ::cdev:vxfs: (cdev
being an acronym for character device), the file is treated as if it were a raw device. For example, if
the file temp01 is a regular VxFS file, then an application can access temp01 as a raw character
device by opening it with the name:
.temp01::cdev:vxfs:
Note We recommend reserving the ::cdev:vxfs: extension only for Quick I/O files. If you
are not using Quick I/O, you could technically create a regular file with this extension;
however, doing so can cause problems if you later enable Quick I/O.
How to Set Up Quick I/O
Quick I/O is part of the VxFS binaries shipped with VERITAS Storage Foundation for Oracle. By
default, Quick I/O is enabled when you mount a VxFS file system.
If Quick I/O is not available in the kernel, or the VERITAS Storage Foundation for Oracle license
is not installed, a file system mounts by default without Quick I/O, the Quick I/O file name is
treated as a regular file, and no error message is displayed. If, however, you specify the -o qio
option, the mount command prints the following error message and terminates without mounting
the file system.
VxFDD: You don’t have a license to run this program
vxfs mount: Quick I/O not available