Dmitry Russ (Aleksandrov)
Из-за того, как он работает с concurency.
если интересно, побщался в эликсировском слаке с разработчиком commanded (slashdotdash), вот его ответ по поводу параллелизма:
That is true for each individual event handler and process manager. My advice for slow event processing would be to have the handler delegate the work to a background job queue which can be as concurrent as necessary.
On the roadmap for Commanded is to use Broadway for concurrency (and batching).
Another option to consider now is to manually partition event handling by starting multiple instances and have them process a subset of events (e.g. start four handlers and have each handler process 1/4 of the events). (edited)
в общем советует паралелить джобы ручками, как вы и собираетесь.