Control the number of worker threads available to the global task manager which can
then assign the threads to process tasks scheduled by SAP Replication Server
modules.
When SAP Replication Server starts, it creates a global task manager that creates the
number of worker threads you set with the worker_thread_num parameter
at the server level for all connections. The global task manager makes the threads
available for tasks scheduled by modules such as distributed application of transactions
in DSI and parallel processing in DIST.
The default number of worker threads is 4, the maximum you can set is 32 and the minimum
is 2.
Recommendations for Tuning the Number of Worker Threads
The default setting for
worker_thread_num is
applicable to most replication environments.
- Tune the number of worker threads only when you enable parameters that use
worker threads such as when you enable distributed application of
transactions in DSI or parallel processing in DIST.
- If you want to change the number of worker threads, set a value to match the
number of CPU cores assigned to the SAP Replication Server process on the
host machine. For most environments, worker_thread_num
should be smaller than the number of CPU cores assigned.
- Tune the number of worker threads after you observe the worker thread
activity over time using admin who. If you see the Active
status for the majority of worker threads for most of the observation time,
you can increase worker_thread_num to improve
performance. If you see that most of the worker threads are in the Waiting
or Inactive status for most of the time, you can decrease
worker_thread_num to conserve resources.