Kafka parallel consuming

For very large topics when you need more parallelism (especially on the insert side) you may use several tables with the same pipeline (pre 20.9) or enable kafka_thread_per_consumer (after 20.9).

kafka_num_consumers = N,


  • the inserts will happen in parallel (without that setting inserts happen linearly)
  • enough partitions are needed.

Before increasing kafka_num_consumers with keeping kafka_thread_per_consumer=0 may improve consumption & parsing speed, but flushing & committing still happens by a single thread there (so inserts are linear).

Last modified 2021.08.24: Code format corrections. (6fe6a9e5c)