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Tencent Cloud Developer

Dec 24, 2021 · Cloud Native

Deep Dive into Apache Pulsar Message Acknowledgment Mechanism

Apache Pulsar ensures reliable delivery by letting consumers acknowledge messages individually, cumulatively, or within batches, while also supporting negative acknowledgments and sophisticated tracking mechanisms that batch ack requests, use BitSet for batch indexes, and employ time‑wheel‑based redelivery for unacknowledged messages.