Veritas File System 4.1 Administrator's Guide (HP-UX 11i v3, February 2007)

Quick I/O for Databases
Creating a Quick I/O File Using qiomkfile
Chapter 11150
Creating a Quick I/O File Using qiomkfile
The best way to make regular files accessible to the Quick I/O interface and preallocate space for them is to
use the qiomkfile command. Unlike the VxFS setext command, which requires superuser privileges,
any user who has read/write permissions can run qiomkfile to create the files. The qiomkfile
command has five options:
-a Creates a symbolic link with an absolute path name for a specified file. The default is to
create a symbolic link with a relative path name.
-e Extends the file size by the specified amount.(For Oracle database files to allow
tablespace resizing.)
-h Creates a file with additional space allocated for the Oracle header.(For Oracle database
files.)
-r Creates a file with additional space allocated for the Oracle header.(For Oracle database
files.)
-s Preallocates space for a file.
You can specify file size in terms of bytes (the default), or in kilobytes, megabytes, gigabytes, or sectors
(512 bytes) by adding, a k, K, m, M, g, G, s or S suffix. If the size of the file including the header
is not a multiple of file system block size, it is rounded to a multiple of the file system block size before
preallocation.
The qiomkfile command creates two files: a regular file with preallocated, contiguous space and a
symbolic link pointing to the Quick I/O name extension. For example, to create a 100 MB file named
dbfile in /database, enter:
$ qiomkfile -s 100m /database/dbfile
In this example, the first file created is a regular file named /database/.dbfile (whichhas the real space
allocated).
The second file is a symbolic link named /database/dbfile. This is a relative link to /database/dbfile
via the Quick I/O interface, that is, to .dbfile::cdev:vxfs:. This allows .dbfile to be accessed by any
database or application as a raw character device. To check the results, enter:
$ ls -al
-rw-r--r-- 1 oracle dba 104857600 Oct 22 15:03 .dbfile
lrwxrwxrwx 1 oracle dba 19 Oct 22 15:03 dbfile -> \
.dbfile::cdev:vxfs:
or: