Introduction
Analytical workloads at scale demand architectures that are not only fast, but also cost-efficient and elastic. Apache Iceberg has emerged as the de facto standard for big-data storage on object stores, offering features like ACID compliance, time travel, and schema evolution – all without the overhead of rewriting large files. While ClickHouse’s MergeTree family has long been celebrated for its performance, its traditional engines often rely on local storage or tightly coupled orchestration layers.
Enter two modern approaches aiming to solve this challenge: Altinity’s Project Antalya and ClickHouse Cloud’s SharedMergeTree.
Altinity’s Project Antalya is a fully open-source (Apache 2.0 licensed) branch of Altinity’s ClickHouse that brings “infinitely scalable” query performance to Iceberg-backed object storage. It promises up to 10× lower storage costs by cleanly decoupling compute and storage, while embracing cloud-native architecture principles.
In contrast, ClickHouse Cloud’s SharedMergeTree is a powerful, but proprietary storage engine that offers high throughput and elastic compute-storage separation. However, it’s cloud-exclusive and closed-source, limiting transparency and community involvement.
This article explores both solutions, highlights the long-term advantages of open-source architectures.
Project Antalya: Open-Source, Iceberg-Backed Analytics
What Is Project Antalya?
Launched April 16, 2025, Project Antalya is an Altinity-maintained branch of ClickHouse that integrates native query processing with Apache Iceberg tables on S3-compatible object storage.
Core Features
- Stateless Query Swarms: Horizontally scale stateless ClickHouse servers for query and ingest workloads.
- Iceberg Integration: Leverage Iceberg snapshots and metadata for transparent query across native MergeTree and Iceberg tables.
- 10× Cheaper Storage: Offload data to cost-effective object storage, reducing storage bills by an order of magnitude.
- Cloud-Native Clustering: Separate compute and storage entirely, enabling independent scaling of each layer.Explo
Open-Source Commitment
All Antalya examples, binaries, and documentation are available under the Apache 2.0 license on GitHub, with zero feature hold-backs and a public issue tracker inviting contributions.
ClickHouse Cloud’s SharedMergeTree: Proprietary Power
Engine Overview
SharedMergeTree is a drop-in replacement for ReplicatedMergeTree in ClickHouse Cloud, optimized for shared object storage (S3, GCS, Azure Blob) and delivering higher insert throughput and faster merges.
Closed-Source Model
Despite its performance benefits, SharedMergeTree isn’t part of the open-source ClickHouse codebase; its implementation remains proprietary to ClickHouse Inc., limiting community auditability and contributions.
Open vs. Proprietary: Key Considerations
- License:
- Project Antalya is fully open source under the Apache 2.0 license.
- SharedMergeTree is closed-source and exclusive to ClickHouse Cloud.
- Storage Format:
- Antalya supports Apache Iceberg on S3-compatible object storage.
- SharedMergeTree uses object storage but doesn’t support open table formats like Iceberg.
- Compute Scaling:
- Antalya enables stateless swarm clusters for independent scaling of compute.
- SharedMergeTree operates on managed compute nodes within ClickHouse Cloud.
- Community Involvement:
- Antalya has a public GitHub repository with active community contribution.
- SharedMergeTree is developed internally with no external visibility or contributions.
- Cost Efficiency:
- Antalya promises up to 10× cheaper storage by leveraging open formats and decoupled architecture.
- SharedMergeTree offers performance and comes with proprietary cloud pricing.
Why Open Source Matters
- Transparency & Security: Open code enables rapid discovery and remediation of bugs or vulnerabilities.
- Innovation & Extensibility: Community contributions drive feature diversity and faster roadmap progression.
- Vendor Neutrality: Avoid lock-in; deploy anywhere from self-managed setups to any cloud.
Enterprises increasingly choose open-source table formats like Iceberg to ensure long-term control over their data infrastructure.
Congratulations to Altinity
We applaud Altinity for releasing Project Antalya as fully open source. This initiative not only tackles cost and scalability challenges head-on but also reinforces the ethos of collaborative innovation in the ClickHouse ecosystem. Kudos to the Altinity team for empowering users worldwide to build, extend, and secure their analytical platforms without compromise!
Disclaimer: Quantrail Data is an independent entity and is not affiliated, associated, authorized, endorsed by, or in any way officially connected with Altinity Inc, ClickHouse Inc., or any of their subsidiaries or affiliates. All product names, logos, and brands mentioned are the property of their respective owners and are used for identification purposes only.
References
Photo by cottonbro studio from Pexels: https://www.pexels.com/photo/man-and-woman-in-their-game-character-costumes-7780086/
https://clickhouse.com/docs/cloud/reference/shared-merge-tree#enabling-sharedmergetree