Database Analyzer task

Tasks for Database Analyzer

Database Analyzer tasks are taken from the floating service task pool, which is limited by the FloatingServiceTasks parameter. More information: Support Parameter

Event task

Tasks for events

Event tasks are also taken from the floating service task pool, which is limited by the FloatingServiceTasks parameter.

Floating Service task

Database Analyzer and Event tasks are taken from the floating service task pool, which is limited by the FloatingServiceTasks parameter.

Idle task

Used for internal task scheduling

Log Writer

Log Writers write log entries from the log queue to the log area, for example after a COMMIT or during a savepoint.

There is a log writer for each log partition. More information: Log Area

You define the maximum number of log writers with the special database parameter MaxLogWriterTasks. More information: Special Database Parameters

Pager (formerly Data Writer)

Pagers write the data from the data cache to the data volumes at each savepoint. Writing a savepoint can take a long time for a large data cache. If necessary, Pagers also become active between savepoints, to write the changed data asynchronously.

During a restart of the database, Pagers read the converter pages from the data volumes into the converter.

The system calculates the number of Pagers required. It is primarily dependent on the size of the data cache and the number of data volumes.

Server task

Server tasks parallelize database functions. They are required, for example, to back up data and log entries, create indexes and to permanently delete tables. During a restart of the database, Server tasks import log entries and process transactions in parallel.

You can configure the number of Server tasks that are available using the MaxServerTasks special database parameter.

Server tasks can have special names that reflect how they are used, for example Savepoint, BackupMedium, BackupVolume, AutosaveCoordinator, AutosaveMedium.

Timer task

The Timer task is responsible for time-outs of SQL lock requests and checks whether log entries can be backed up.

Trace Writer task

The Trace Writer task writes the trace entries in the working memory when the database trace is switched on.

User task

User tasks execute SQL statements.

When a database user opens a database session, the database system assigns one User task to this database user.

User tasks create the main load for the processor.

You can configure the number of available User tasks using the special database parameter MaxUserTasks.

Utility task

The Utility task performs administration tasks.