Can Kafka Queues Make Consumers Faster? Part 2: Head-Of-Line Blocking

2026-05-14

Kafka Queues (Share Groups) shine when consumer processing involves delays or external I/O that causes Head-Of-Line Blocking. By allowing more consumer instances than partitions, share groups enable linear scaling of throughput (tested up to 8x with 32 instances) with no noticeable per-instance overhead, making them very effective for I/O-bound workloads.