The following
overview describes the general database
parameters. For more information about other database parameters, see Special Database
Parameters, Support Database
Parameters and liveCache
Parameters.
Changes to database parameters do not take effect until the database instance is restarted.
General database parameters
Parameter |
Description |
CACHE_SIZE |
Size of the I/O Buffer Cache (in pages) |
INSTANCE_TYPE |
Database instance type; defined when the database instance is created and cannot be changed later. |
KERNELVERSION |
Version of the database software; this parameter is changed implicitly if a new version of the database software is installed. |
LOG_MIRRORED |
Specifies whether the log area is mirrored (Log Mode). The parameter is relevant only for creating a mirror volume using Database Manager CLI. When a mirror volume is created using the Database Manager GUI, this value is changed implicitly. |
LOG_SEGMENT_SIZE |
Size of a log segment (in pages). If a log segment is full, a lock backup is started automatically, if this option is activated. |
MAXBACKUPDEVS |
Maximum number of files or tape devices in a group of parallel backup media |
MAXCPU |
Maximum number of processors to which the database system can distribute user tasks. Note that your computer’s operating system resources have to be available for other processes, not only for the database system. |
MAXDATAVOLUMES |
Maximum number of data volumes |
MAXLOCKS |
Maximum number of entries in the lock list |
MAXLOGVOLUMES |
Maximum number of log volumes |
MAXUSERTASKS |
Maximum number of user tasks that are active at the same time and therefore the maximum number of database sessions. If this number is reached, then no additional users can log onto this database instance. We recommend that you monitor MAXUSERTASKS. Overconfiguration leads to increased address space requirement (particularly when using shared memory). |
MCOD |
MCOD = Multiple Components One Database; indicates whether the database is being used by more than one application (for SAP systems). |
RESTART_SHUTDOWN |
Specifies whether the database instance automatically transferred to the ONLINE operational state when the operating system is started, and if it should be stopped automatically when the operating system is shut down. |
RUNDIRECTORY |
Run directory on the database instance |