AutoLogBackupSize

LOG_SEGMENT_SIZE

Log segment size (in pages)

When automatic log backup is activated and no time interval has been configured, then the database system starts an automatic log backup as soon as a log segment is full.

0: system uses 1/3 of the log area as the log segment size

≤50% of the log area: system uses the value defined in AutoLogBackupSize

> 50% of the log area: system uses 50% of the log area as the log segment size

Changes only apply after a restart of the database.

Database Administration, Backing Up Log Entries

BridgeType

-

Specifies whether the database is used in a bridge scenario (where the database acts as a bridge to other databases)

Changes only apply after a restart of the database.

CacheMemorySize

CACHE_SIZE

Size of the working memory (RAM) which is used by the database system for I/O operations (in pages).

The main consumers of the working memory area configured with CacheMemorySize are the data cache, the converter, the shared catalog cache and the file directory; but other database components also use this memory area.

The following restrictions apply: 800 ≤ CacheMemorySize < total RAM size

This parameter has a great impact on the performance of your system. The optimum value for this parameter depends on your system environment. Note that other database functions and programs also need a certain amount of working memory, so do not assign your whole working memory to CacheMemorySize.

Changes only apply after a restart of the database.

Database Administration, Analyzing Database Performance

Concepts of the Database System, Working Memory Areas

InstanceType

INSTANCE_TYPE

Database type:

You define the database type when you create the database.

Cannot be changed

Concepts of the Database Systems,

KernelVersion

KERNELVERSION

Version of the database software

You cannot change this value.

When you install a new version of the database software, the database system updates the value of this parameter.

MaxBackupMedia

MAXBACKUPDEVS

Maximum number of files or tape devices for parallel backup

Changes only apply after a restart of the database.

Database Administration, Backup Templates and Data Carriers

MaxCPUs

MAXCPU

Maximum number of processors to which the database system can distribute user tasks.

When choosing this value, bear in mind that your computer's operating system resources have to be available for other programs as well.

To further restrict the number of available CPUs in a running system, use the special database parameter UseableCPUs.

Changes only apply after a restart of the database.

SAP Note 936058

MaxDataVolumes

MAXDATAVOLUMES

Maximum number of data volumes

Changes only apply after a restart of the database.

Concepts of the Database System, Volumes (Permanent Storage)

MaxLogVolumes

MAXLOGVOLUMES

Maximum number of log volumes

Changes only apply after a restart of the database.

MaxSQLLocks

MAXLOCKS

Maximum number of locks for database objects

Changes only apply after a restart of the database.

Concepts of the Database System, Locks

MaxUserTasks

MAXUSERTASKS

Maximum number of simultaneously active user tasks and therefore the maximum number of database sessions

If this number has been reached, then no additional user can log on to the database.

Note that if you choose a large value for MaxUserTasks, the database system requires much address space, particularly for local communication via shared memory.

For SAP systems (OLTP), we recommend the following minimum value: 2 x <number_of_SAP_processes> + 4

Changes only apply after a restart of the database.

Concepts of the Database System, Tasks

SAP Note 757914

MCODIndicator

MCOD

MCOD = Multiple Components One Database

In SAP systems, this parameter indicates whether several applications are using this database.

Changes only apply after a restart of the database.

OmsMaxHeapSize

OMS_HEAP_LIMIT

For SAP liveCache databases

Specifies the maximum size of the OMS heap (in KB)

Changes only apply after a restart of the database

-

RunDirectoryPath

RUNDIRECTORY

Run directory of the database

If you specify a relative path, the system interprets this path relative to the data path:

<global_data_path>\wrk\<database_name>\ or<private_data_path>\wrk\<database_name>\ (if you have configured a private data path during installation)

Changes only apply after a restart of the database.

Glossary, Run Directory

UseMirroredLog

LOG_MIRRORED

Specifies whether the database system mirrors the log area (software-based mirroring)

This parameter is relevant only when you create a mirror volume using Database Manager CLI. Database Studio automatically adjusts this parameter when you create a mirror volume.

Note that it we recommend to use hardware-based mirroring for the log area. More information: Planning Databases

Changes only apply after a restart of the database.

Glossary, Log Mode

Active Value

Active value

New value

New value

Durability

(Not available for all database parameters)