Veritas Storage Foundation 5.1 SP1 Advanced Features Administrator"s Guide (5900-1503, April 2011)

■ The qiomkfile command creates two files: a regular file with

preallocated, contiguous space, and a file that is a symbolic link

pointing to the Quick I/O name extension.

■ See the qiomkfile(1M) manual page for more information.

Usage notes

Creates a symbolic link with an absolute path name for a specified

file. Use the -a option when absolute path names are required.

However, the default is to create a symbolic link with a relative path

name.

-a

Extends a file by a specified amount to allow DB2 tablespace resizing.

See “Extending a Quick I/O file in a DB2 environment” on page 51.

-e

Increases the file to a specified size to allow DB2 tablespace resizing.

See “Extending a Quick I/O file in a DB2 environment” on page 51.

-r

Specifies the space to preallocate for a file in bytes, kilobytes,

megabytes, gigabytes, or sectors (1024 bytes) by adding a k, K, m, M, g,

G, s, or S suffix. The default is bytes—you do not need to attach a suffix

to specify the value in bytes. The size of the file that is preallocated

is the total size of the file (including the header) rounded to the nearest

multiple of the file system block size.

-s

Warning: Exercise caution when using absolute path names. Extra steps may be

required during database backup and restore procedures to preserve symbolic

links. If you restore files to directories different from the original paths, you must

change the symbolic links that use absolute path names to point to the new path

names before the database is restarted.

To create a container as a Quick I/O file using qiomkfile

Create a Quick I/O-capable file using the qiomkfile command:

$ /opt/VRTS/bin/qiomkfile -s file_size /mount_point/filename

Create tablespace containers using this file with the following SQL statements:

$ db2 connect to database

$ db2 create tablespace tbsname managed by database using \

( DEVICE /mount_point/filename size )

$ db2 terminate

41Improving DB2 performance with Veritas Quick I/O

Creating database containers as Quick I/O files using qiomkfile for DB2