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

■ You can create Quick I/O files only on VxFS file systems.
■ To create device files on an existing file system, run fsadm (or
similar utility) to report and eliminate fragmentation.
■ You must have read/write permissions on the directory in which
you intend to create DB2 Quick I/O files.
Prerequisites
■ 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 Sybase environment” on page 72.
-e
Increases the file to a specified size to allow DB2 tablespace resizing.
See “Extending a Quick I/O file in a Sybase environment” on page 72.
-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 Ssuffix. 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. When 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 beforeyou restart the database.
Improving Sybase performance with Veritas Quick I/O
Creating database files as Quick I/O files with qiomkfile
60