ClickStack vs Fluentd

ClickStack is an open-source observability stack for OpenTelemetry that brings logs, metrics, traces, session replays, and errors into one system. Its HyperDX interface provides Lucene-style search, SQL access, dashboards, alerts, event deltas, and event patterns. A bundled OpenTelemetry Collector handles native collection, while non-OTel wide event data can be used when it has a timestamp field. ClickStack stores data in ClickHouse and is designed for high-cardinality telemetry, with the product site describing sub-second queries even on petabytes of data. It supports self-hosted, hybrid, and cloud deployment. Managed ClickStack runs on ClickHouse Cloud with operations, scaling, upgrades, backups, reliability, authentication, and user management included. The managed offer advertises indefinite retention and storage below one cent per GB. An MCP server connects observability workflows with coding tools, collaboration services, runbooks, and custom agents.

Fluentd is a free, open-source data collector for creating a unified logging layer. It uses JSON to handle log collection, filtering, buffering, and output across sources and destinations. More than 500 community plugins connect it to data sources and outputs, including Elasticsearch and Kibana, Splunk, AWS S3, Kafka, BigQuery, Datadog, and OpenTelemetry. It supports memory and file buffering, failover, and high availability to help prevent data loss between nodes. The project reports that a vanilla instance uses 30–40 MB of memory and can process 13,000 events per second per core. Fluentd v1 runs on Linux, Mac OSX, and Windows; community distributions also include Docker images, a Kubernetes DaemonSet, and Ruby gems. It is self-hosted, and its components are available under the Apache 2 License. The project lists community help and commercial support from companies offering enterprise services. The homepage notes vulnerabilities patched in Fluentd v1.19.3 and advises updating fluent-package to v6.0.4.