Device allocation and object placement

When configuring a new system, the System Administrator must consider several issues that have a direct impact on the number and size of disk resources required. These device allocation issues refer to commands and procedures that add disk resources to Adaptive Server. Device allocation topics are described in the chapters shown in Table 15-1.

**Table 15-1: Device allocation topics**
Task	Chapter
Initialize and allocate a default pool of database devices.	Chapter 16, “Initializing Database Devices”
Mirror database devices for recovery.	Chapter 17, “Mirroring Database Devices”

After the initial disk resources have been allocated to Adaptive Server, the System Administrator, Database Owner, and object owners should consider how to place databases and database objects on specific database devices. These object placement issues determine where database objects reside on your system and whether or not the objects share devices. Object placement tasks are discussed throughout this manual, including the chapters shown in Table 15-2.

**Table 15-2: Object placement topics**
Task	Chapter
Place databases on specific database devices.	Chapter 21, “Creating and Managing User Databases”
Place tables and indexes on specific database devices.	Chapter 24, “Creating and Using Segments”

Do not consider allocating devices separately from object placement. For example, if you decide that a particular table must reside on a dedicated pair of devices, you must first allocate those devices to Adaptive Server. The remaining sections in this chapter provide an overview that spans both device allocation and object placement issues, providing pointers to chapters where appropriate.