Setting database page size values

The next dialog prompts you for the database page size values. The page size you select affects the performance of the database. For this tutorial, use the page size recommendations for each category listed below, then click Next.

Specify the page size

IQ store Size

When the shared IQ store is on a raw partition, the IQ Store Size box disappears because Sybase IQ determines the size of the raw device and sets IQ SIZE to that value.

When the IQ store is a file, the default store size is 1000MB, but for this tutorial, use 10MB.

Reserve space

For this tutorial, leave the Reserve size blank. Reserve space allows the size of the dbfile to be increased later using the ALTER DBSPACE ... ALTER FILE ADD|SIZE command. Generally, the amount of Reserve space you allow depends on how much space your hardware supports. If the dbspace partition is a single disk, you should never need more reserve than the largest disk currently available. If the partition is on a disk array, the size of a single partition could be much large, since a disk array can have a single partition that uses many disks.

IQ page size

Accept the IQ page size supplied, or choose one from the dropdown box. The Create Database wizard supplies an appropriate default page size in the IQ Page Size box.

See the System Administration Guide: Volume 1 and System Administration Guide: Volume 2 for more information. For this example, click Next to accept the default IQ page size (128KB).

Table 4-2: Default and minimum sizes of Sybase IQ and temporary stores

IQ page size

Default size of IQ store

Default size of temporary store

Minimum IQ store size when specified explicitly

Minimum temporary store size when specified explicitly

65536

4096000

2048000

4MB

2MB

131072

8192000

4096000

8MB

4MB

262144

16384000

8192000

16MB

8MB

524288

32768000

16384000

32MB

16MB

Database page size

Select a Database Page Size for the catalog store. (The catalog store holds the metadata for Sybase IQ.) The default is 4096 bytes (4KB). Sybase recommends that you use this default.