IBM 000-8697 Manual Do Utilizador

Installation and Initial Configuration

The amount of additional disk space needed for OnLine data storage
depends on your production environment. Every application environment is
different. The following list suggests some of the steps you might take to help
you calculate the amount of disk space to allocate (beyond the root dbspace):

Decide how many databases and tables you need to store. Calculate
the amount of space required for each one.

Calculate a growth rate for each table and assign some amount of
disk space to each table to accommodate growth.

Decide which databases and/or tables you want to mirror.

Refer to

utorial for instructions about calculating

the size of your data bases.

After you arrive at a value, enter it on the second page of the configuration
worksheet, in the field labeled Additional disk space for OnLine chunks.

When you allocate disk space (raw disk or cooked files), you allocate it in
units called chunks. A dbspace or a blobspace is associated with one or more
chunks. You must allocate at least one chunk for the root dbspace.

(Refer to

 for a discussion of the relationships among chunks,

dbspaces, blobspaces, databases, and tblspaces.)

Informix recommends that you format your disk(s) so that each chunk is
associated with its own

UNIX

disk partition. When every chunk is defined as

a separate partition (or device), you will find it is easy to track disk space
usage. You avoid errors caused by miscalculated offsets.

If you are working with a disk that is already partitioned, you might be
required to use offsets to define a chunk.