Planning for DB2

You can use a new or existing DB2® infrastructure. Ensure that an appropriate amount of disk space is available for your DB2 environment, and allocate memory accordingly.

You can use the DB2 installation that comes with IBM® Sametime®, or you can use an existing DB2 infrastructure. Check the IBM Sametime System Requirements for releases of DB2 supported.

Disk requirements

The disk space required depends on the type of installation you choose and the type of file system you have. The DB2 Setup wizard provides dynamic size estimates based on the components selected during a typical, compact, or custom installation. Remember to include disk space for required databases, software, and communication products. On Linux™ and UNIX™ operating systems, 2 GB of free space in the /tmp directory is recommended.
Note: On Linux and UNIX operating systems, you must install your DB2 product in an empty directory. If the directory that you have specified as the install path contains subdirectories or files, your DB2 installation might fail.

Memory requirements

Memory requirements are affected by the size and complexity of your database system, the extent of database activity, and the number of clients accessing your system. At a minimum, a DB2 database system requires 256 MB of RAM. For a system running just a DB2 product and the DB2 GUI tools, a minimum of 512 MB of RAM is required. However, 1 GB of RAM is recommended for improved performance. These requirements do not include any additional memory requirements for other software that is running on your system. For IBM data server client support, these memory requirements are for a base of five concurrent client connections. For every additional five client connections, an additional 16 MB of RAM is required. For DB2 server products, the self-tuning memory manager (STMM) simplifies the task of memory configuration by automatically setting values for several memory configuration parameters. When enabled, the memory tuner dynamically distributes available memory resources among several memory consumers including sort, the package cache, the lock list, and buffer pools.

For information about configuring DB2 for high availability, see the DB2 product documentation. For example, refer to Configuring a clustered environment for high availability.

For information about backing up DB2 data, see the DB2 product documentation, for example, see Backup overview. For information about backing up DB2 data when migrating to a newer version of Sametime, see Backing up DB2 databases.

For information about storage, see the DB2 product documentation, for example, see Storage groups.