Parallelized background tasks

Last modified 18 Mar 2021 17:18 +01:00

Some background tasks, namely initial import and reconciliation could take a considerable time. If you have a multicore machine, it is reasonable to try to use its processing power to make these tasks proceed faster.

MidPoint has a simple feature to allow this: parallelized background tasks. It is applicable to the following tasks:

  • import,

  • reconciliation,

  • recomputation,

  • iterative bulk actions (see Scripting tasks),

  • reindex.

All you have to do is to set workerThreads extension property, like this:

<extension xmlns:mext="">

(or edit the task in midPoint GUI)

When such a task is started, it is run in 9 threads: one is so called coordinator thread that fetches data from the resource or from the repository and feeds remaining 8 worker threads. Each worker thread processes item by item (e.g. shadow by shadow) until all items are processed. At that point the processing ends and all threads are destroyed.

If workerThreads property is not set or set to 0, the whole processing takes place in a single thread: no dedicated worker threads are created. If the value is 1, one coordinator and one worker is created (so this setting is not useful).

Technically, the feature is implemented in AbstractSearchIterativeResultHandler that takes care of processing results from iterative searches conducted by these tasks. Worker threads can be seen when you open particular task in Task List menu. They exist only during the run of a particular task, and are visible only when logged in to the node on which they run. Lightweight asynchronous tasks were created just for this purpose.