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DirectoryData & AnalyticsStreaming & Real-Time AnalyticsPulsar

Pulsar

About Pulsar

Apache Pulsar is an open-source, distributed messaging and streaming platform built for the cloud. It is described as an all-in-one messaging and streaming platform. Messages can be consumed and acknowledged individually or as streams. Its layered architecture allows scaling across hundreds of nodes without data reshuffling. Features include multi-tenancy, geo-replication, tiered storage, and support for six official client languages. It supports up to one million unique topics.

Used for

  • Submitting tasks to run and ensuring execution including error handling.
  • Using topics for indirect API communication among micro-services.
  • Running mission-critical applications requiring failure resiliency.
  • Streaming data in or out via third-party connectors such as MySQL, Elasticsearch, and Cassandra.

Who it is for

  • Has a user base spanning small companies and large enterprises.

From Pulsar's own website, read 2026-10-23. How we build listings.

How to evaluate Streaming & Real-Time Analytics

This is how the CIOPages Research Team evaluates this category. It is not an assessment of Pulsar. It comes from our Streaming Data & Event Processing buyer guide.

25%
Throughput, Latency & Durability
Sustained throughput and tail latency at your partition count, ordering and exactly-once / at-least-once delivery guarantees, replication and multi-AZ durability, retention limits, and behavior under broker failure and rebalancing
20%
Operating Model & Architecture
Self-managed vs. fully managed vs. serverless vs. bring-your-own-cloud, KRaft (post-ZooKeeper) operations, diskless / object-storage-backed options, autoscaling, partition rebalancing, and upgrade and patching burden on your team
20%
Kafka-API Compatibility & Portability
Fidelity of the Kafka protocol (consumer groups, transactions, compaction), reuse of existing clients, connectors and tooling, lock-in to a single cloud, and the realistic effort to migrate in or out
15%
Stream Processing & Ecosystem
Native or integrated processing (Flink, Kafka Streams, Spark Structured Streaming, ksqlDB), connector catalog (CDC, sinks, sources), schema registry and governance, and direct landing into Iceberg / Delta lakehouse tables
10%
Security, Governance & Compliance
Encryption in transit and at rest, mTLS / SASL / OAuth and RBAC, audit logging, private networking, data residency and BYOC data-boundary control, and SOC 2 / ISO 27001 / GDPR coverage
10%
Cost Model & Economics at Scale
Pricing unit (capacity / throughput / consumption), inter-AZ and egress charges, storage and retention cost, processing billed separately, and how the bill behaves as volume, partitions, and connectors grow

CIOPages put this listing together from public sources. It’s information, not an endorsement. How we build listings. Work here? Claim this listing or .

Quick Facts

pulsar.apache.org
CategoryData & Analytics
SubcategoryStreaming & Real-Time Analytics
PricingOpen source

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