Apache Ignite
activeby Apache Software Foundation · since 2015 · also known as Ignite
A distributed, memory-first SQL database and compute grid; Ignite 3 rebuilt it around Raft and Calcite.
Overview
Apache Ignite started as an in-memory data grid and grew into a distributed database with durable native persistence, ANSI SQL, ACID transactions and collocated compute. Ignite 3 (3.0 in 2025, 3.1 in late 2025) is a ground-up rewrite with Raft-based replication, an Apache Calcite SQL engine, schema-first tables and zone-based replication, while the 2.x line (2.18 in April 2026) remains the long-term-support branch most production clusters still run. It suits workloads that need SQL plus key-value access over a sharded, memory-speed dataset, and teams willing to invest in tuning a distributed JVM system.
Strengths & trade-offs
Strengths
- +Distributed ACID transactions and SQL over memory-speed partitions
- +Collocated compute sends code to the data instead of moving data
- +Native persistence lets the cluster restart without warming from another store
- +Ignite 3 brings Raft replication and a Calcite-based SQL planner
- +Apache-licensed with a commercial backer (GridGain)
Trade-offs
- −Ignite 2 to 3 is a breaking migration with different APIs and storage
- −Operationally heavy: JVM tuning, rebalancing and baseline topology
- −Smaller and slower-moving community than it had in the late 2010s
- −Documentation is split between 2.x and 3.x
Great for
- +Accelerating legacy RDBMS with an in-memory SQL cache layer
- +Real-time risk and pricing calculations
- +Distributed caching with SQL queries over cached data
- +HTAP workloads on a sharded JVM cluster
Think twice for
- −Simple key-value caching (Redis/Valkey is lighter)
- −Small teams without JVM operations expertise
- −Analytical scans over petabytes
Capabilities
Native or official first-party support · 13 of 25 tracked
Scale & consistency
- Comfortable data size
- Large · ≤ 1 PB
- Horizontal scaling
- Native
- Multi-region
- No
- Transactions
- Full ACID
- Consistency
- Strong
- Schema
- Strict
- Architecture
- In memory, Distributed, Embedded, Client server
- Query languages
- SQL, Key-value API
Partitioned tables across many nodes with optional native persistence; datasets can exceed RAM when persistence is on.
Deployment
Ecosystem
Alternatives to Apache Ignite
The commercial, enterprise-hardened distribution of Apache Ignite for low-latency SQL and compute.
apache-ignite vs gridgain →A Java in-memory data grid and stream processor that embeds in your app or runs as a cluster.
apache-ignite vs hazelcast →Oracle's long-running Java data grid, with a UPL-licensed Community Edition on GitHub.
apache-ignite vs oracle-coherence →Red Hat's open-source distributed cache and key-value store, embeddable or as a RESP-compatible server.
apache-ignite vs infinispan →The open-source core of GemFire: a consistent, partitioned in-memory data grid for Java.
apache-ignite vs apache-geode →In-memory, partitioned SQL engine running Java stored procedures serially for millisecond decisioning.
apache-ignite vs volt-active-data →Apache Ignite FAQ
What is Apache Ignite?
Apache Ignite is a key-value database by Apache Software Foundation, first released in 2015. Apache Ignite started as an in-memory data grid and grew into a distributed database with durable native persistence, ANSI SQL, ACID transactions and collocated compute. Ignite 3 (3.0 in 2025, 3.1 in late 2025) is a ground-up rewrite with Raft-based replication, an Apache Calcite SQL engine, schema-first tables and zone-based replication, while the 2.x line (2.18 in April 2026) remains the long-term-support branch most production clusters still run. It suits workloads that need SQL plus key-value access over a sharded, memory-speed dataset, and teams willing to invest in tuning a distributed JVM system.
Is Apache Ignite open source?
Yes. Apache Ignite is open source. License: Apache License 2.0.
Does Apache Ignite support ACID transactions?
Yes. Apache Ignite supports full ACID transactions, with strong consistency.
Does Apache Ignite scale horizontally?
Apache Ignite scales horizontally out of the box, with built-in sharding or partitioning. It is comfortable at large scale (≤ 1 PB).
How can I run Apache Ignite?
You can self-host it and embed it in your application.
What is Apache Ignite best for?
Apache Ignite is a strong fit for accelerating legacy RDBMS with an in-memory SQL cache layer; real-time risk and pricing calculations; and distributed caching with SQL queries over cached data. Think twice for simple key-value caching (Redis/Valkey is lighter).
What are the best alternatives to Apache Ignite?
Common alternatives to Apache Ignite include GridGain, Hazelcast, Oracle Coherence, Infinispan and Apache Geode. The right choice depends on your workload, scale and hosting; WhichDB's smart match ranks them against your requirements.
How popular is Apache Ignite?
Apache Ignite ranks #98 of 844 databases on the WhichDB Score (28.3/100), and #16 among key-value databases. The score combines public adoption signals such as package downloads, GitHub activity, job posts and developer discussion.