User Kernel Thread 

A user kernel thread (UKT) bundles a range of tasks that fulfill various functions. The following task types can run in a user kernel thread:

·        Pager

·        Log writer

·        Server task

·        Timer task

·        Trace writer task

·        User task

·        Utility task

Several user kernel threads are generated when a database instance is started. The number of user kernel threads and the number and type of tasks that can run in a user kernel thread are specified in database parameters.