SeaweedFS

SeaweedFS is a lightweight, horizontally‑scalable object storage and file server written in Go. It exposes a POSIX‑like filesystem API over HTTP/REST, S3‑compatible endpoints, and native Go client libraries. Internally it partitions data into volume servers that store raw bytes in a contiguous allocation scheme, while a lightweight master maintains namespace metadata and volume placement. The architecture is deliberately simple: each volume server runs a single process, allowing thousands of them to be orchestrated with Kubernetes or Docker Compose without the need for a complex distributed filesystem layer.

Key Features

• Low‑latency, high‑throughput: The volume servers write data sequentially to local SSDs or memory, achieving sub‑millisecond latency for small objects and sustained terabyte per second throughput on commodity hardware.
• Global namespace: The master keeps a consistent mapping from file paths to volume IDs in an embedded key‑value store (etcd or RocksDB), enabling fast lookups and atomic updates.
• S3 & HTTP APIs: Developers can integrate SeaweedFS with existing tooling by consuming its RESTful API or using the official S3 client SDKs available on Maven Central and Go modules.
• Rolling upgrades: Because the master is stateless, you can hot‑swap volume servers or upgrade binaries without downtime.

Technical Stack

• Language: Go 1.20+ (fully static binaries).
• Storage backend: Native file system on SSD or RAM; optional integration with MinIO for S3‑compatible backing.
• Metadata store: Embedded RocksDB or optional etcd cluster; replication is achieved via Raft.
• Networking: gRPC for internal communication, HTTP/REST for client access; TLS support is optional.
• Containerization: Official Docker images are available, and Helm charts simplify deployment on Kubernetes.

Deployment & Infrastructure

SeaweedFS can be self‑hosted on a single node for development or scaled to thousands of nodes in production. Each volume server consumes minimal resources (≈1 GB RAM + local disk), so you can pack dozens per machine. The master is lightweight (≈50 MB RAM) and can run on a dedicated node or within the same cluster. For high availability, run at least three masters in an etcd‑based Raft group; the system automatically elects a leader and replicates metadata. Kubernetes operators expose CRDs for SeaweedFS and VolumeServer, allowing declarative scaling, rolling upgrades, and automated health checks.

Integration & Extensibility

SeaweedFS exposes a rich set of APIs:

• REST (/filer, /volume) for CRUD operations.
• S3 API (/s3) compatible with most SDKs.
• Webhooks: Users can register callbacks on file events (upload, delete) via the filer API.
• Plugins: The filer supports custom handlers written in Go, enabling features such as ACL enforcement or metadata enrichment.

The project’s open‑source nature encourages community contributions; the GitHub repository hosts a comprehensive wiki, API documentation on GoDoc, and an active Slack channel for real‑time support.

Use Cases

• High‑performance media CDN: Store and serve millions of video clips with low latency.
• Backup & archival: Immutable object storage that scales horizontally without complex provisioning.
• IoT data ingestion: Handle high‑volume, small‑payload streams from edge devices.
• Hybrid cloud: Run SeaweedFS on-premises and expose it to external services via the S3 API, avoiding vendor lock‑in.

Advantages

Developers choose SeaweedFS for its minimal operational overhead, Go‑native performance, and flexible licensing (Apache 2.0). Unlike monolithic object stores, it requires no external distributed consensus layer beyond the lightweight master, reducing cluster complexity. Its small binary footprint and memory‑efficient design make it ideal for edge deployments or environments with strict resource constraints. The rich API surface and active community ensure rapid integration into existing workflows, while the open‑source model guarantees freedom to modify internals for specialized workloads.