Extending a Quick I/O file

Although Quick I/O files must be preallocated, they are not limited to the preallocated sizes. You can grow or "extend" a Quick I/O file by a specific amount or to a specific size, using options to the qiomkfile command. Extending Quick I/O files is a fast, online operation and offers a significant advantage over using raw devices.

Before extending a Quick I/O file, make sure the following conditions have been met:

Prerequisites

  • You must have sufficient space on the file system to extend the Quick I/O file.

Usage notes

  • You can also grow VxFS file systems online (provided the underlying disk or volume can be extended) using the fsadm command. You can expand the underlying volume and the filesystem with the vxresize command.

  • You must have superuser (root) privileges to resize VxFS file systems using the fsadm command.

  • See the fsadm_vxfs (1M) and qiomkfile (1M) manual pages for more information.

The following options are available with the qiomkfile command:

-e

Extends the file by a specified amount to allow DB2 container resizing.

-r

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

To extend a Quick I/O file

  1. If required, ensure the underlying storage device is large enough to contain a larger VxFS file system (see the vxassist(1M) manual page for more information), and resize the VxFS file system using fsadm command:

    # /opt/VRTS/bin/fsadm -b <newsize> /mount_point

    where:

    • -b is the option for changing size

    • <newsize>is the new size of the file system in bytes, kilobytes, megabytes, blocks, or sectors

    • <mount_point>is the file system's mount point

  2. Extend the Quick I/O file using the qiomkfile command:

    $ /opt/VRTS/bin/qiomkfile -e extend_amount /mount_point/filename

    or

    $ /opt/VRTS/bin/qiomkfile -r newsize /mount_point/filename

    An example to show how to grow VxFS file system /db01 to 500MB and extend the tbs1_cont001 Quick I/O file by 20MB:

    # /opt/VRTS/bin/fsadm -b 500M /db01
    $ /opt/VRTS/bin/qiomkfile -e 20M /db01/tbs1_cont001

    An example to show how to grow VxFS file system /db01 to 500MB and resize the tbs1_cont001 Quick I/O file to 300MB:

    # /opt/VRTS/bin/fsadm -b 500M /db01
    $ /opt/VRTS/bin/qiomkfile -r 300M /db01/tbs1_cont001