Fluentd - Log Collection

Open-source unified logging layer data collector F Cloud Infrastructure

Basic Information

  • Company/Brand: Fluentd (CNCF Graduated Project, maintained by Treasure Data)
  • Founder: Sadayuki Furuhashi
  • Country/Region: Japan/USA
  • Official Website: https://www.fluentd.org/
  • GitHub: https://github.com/fluent/fluentd
  • Type: Open-source unified logging layer data collector
  • Founded: 2011
  • Status: CNCF Graduated Project, 14+ years of history

Product Description

Fluentd is an open-source data collector that provides a unified logging layer to centralize data collection and consumption. As a CNCF Graduated Project, Fluentd is one of the most widely deployed technologies in enterprise log collection. It structures data as JSON whenever possible, unifying all aspects of log collection, filtering, buffering, and output. Fluentd is written in C and Ruby, requiring only 30-40MB of memory, and can process 13,000 events per second per core.

Core Features/Characteristics

  • Unified Logging Layer: Centralizes collection, filtering, buffering, and output of logs from multiple sources
  • 500+ Community Plugins: Connects to dozens of data sources and destinations
  • JSON Structured: Unifies all data into JSON format
  • Lightweight and Efficient: 30-40MB memory, 13,000 events/sec/core
  • Reliable Buffering: Memory and file buffering to prevent data loss
  • Flexible Routing: Tag-based flexible log routing
  • Built-in Reliability: Supports retries on failure and high-availability deployments

Fluent Bit

  • Lightweight version of Fluentd, designed for container and embedded scenarios
  • Written in C, with lower resource consumption
  • CNCF published a migration guide from Fluentd to Fluent Bit in 2025

Business Model

  • Completely Free and Open-source: Apache 2.0 License
  • Treasure Data: Provides commercial log services based on Fluentd
  • Community Support: Through GitHub and community forums

Deployment Methods

  • Package Manager Installation (APT/YUM/Brew)
  • Docker Container
  • Kubernetes DaemonSet
  • Ruby Gem Installation

Target Users

  • Enterprise log platform operations teams
  • Kubernetes operations teams
  • DevOps teams needing log aggregation
  • Organizations requiring unified logs from multiple sources
  • Data pipeline engineers

Competitive Advantages

  • CNCF Graduated Project, 14+ years of history
  • Vast ecosystem with 500+ community plugins
  • Extremely lightweight and efficient
  • Design philosophy of a unified logging layer
  • Extensive enterprise deployment validation
  • Fluent Bit covers lightweight scenarios

Comparison with Competitors

DimensionFluentdLogstashVector
LanguageC+RubyJavaRust
Memory Usage30-40MB1GB+~15MB
Plugin Ecosystem500+200+Growing
CNCFGraduatedNon-CNCFNon-CNCF
PerformanceHighMediumVery High
Best Use CaseEnterprise Log AggregationELK Stack IntegrationHigh-Performance Pipelines

Relationship with OpenClaw Ecosystem

Fluentd is a mature choice for log collection and routing within the OpenClaw ecosystem. It can collect logs from various service components of OpenClaw, unify them into JSON format, and route them to log storage backends like Loki and Elasticsearch. The 500+ plugin ecosystem ensures integration with almost any data source and destination. For resource-constrained scenarios, Fluent Bit is a lighter alternative.

External References

Learn more from these authoritative sources: