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Sybase DC35823-01-1500-04 User Manual

Page 127

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CHAPTER 9 Managing Adaptive Server Databases

Configuration Guide

111

In this example,

"size = 2048"

tells the command to allocate 2048 “virtual”

pages to the device. A virtual page is 2048 bytes, so this command creates a
4MB device.

The example command does not specify a device number, instead letting the
server choose one. Unless you need to assign a specific number to a given
device, Sybase recommends you use this method. If you do need an explicit
device number, use the parameter

"vdevno = N"

, where N is the device

number you want to use. If you specify a device number, that number must not
be in use by any other device on this server. Use

sp_helpdevice

to see what

device numbers have already been used.

If you find an existing database device is too small, you can make that device
larger using the

disk resize

command. This command takes the same “name”

and “size” parameters as

disk init

,except that the “size” parameter specifies how

much larger you want the device to be.

Note

Operating system constraints will limit how much larger you can make

any given device. For example, you cannot make a device on a UNIX raw
partition larger if you have already allocated the full defined size of that
partition.

For more information about

sp_helpdevice

and

disk init

command, see the

System Administration Guide and the Reference Manual.

For more information about device files, see the Performance and Tuning
Guide
.