Cortex

Cortex is a horizontally scalable, highly available, multi-tenant, long-term storage solution for Prometheus and OpenTelemetry Metrics.

Features

• Horizontally scalable: Cortex can run across multiple machines in a cluster, exceeding the throughput and storage of a single machine.
• Highly available: When run in a cluster, Cortex can replicate data between machines.
• Multi-tenant: Cortex can isolate data and queries from multiple different independent Prometheus sources in a single cluster.
• Long-term storage: Cortex supports S3, GCS, Swift and Microsoft Azure for long-term storage of metric data.

Documentation

• Getting Started
• Architecture Overview
• Configuration
• Guides
• Security
• Contributing

Community and Support

If you have any questions about Cortex, you can:

• Ask a question on the Cortex Slack channel. To invite yourself to the CNCF Slack, visit http://slack.cncf.io/.
• File an issue.
• Email cortex-users@lists.cncf.io.

Your feedback is always welcome.

For security issues see https://github.com/cortexproject/cortex/security/policy

Engage with Our Community

We invite you to participate in the Cortex Community Calls, an exciting opportunity to connect with fellow developers and enthusiasts. These meetings are held every 4 weeks on Thursdays at 1700 UTC, providing a platform for open discussion, collaboration, and knowledge sharing.

Our meeting notes are meticulously documented and can be accessed here, offering a comprehensive overview of the topics discussed and decisions made.

To ensure you never miss a meeting, we've made it easy for you to keep track:

• View the Cortex Community Call schedule in your browser here.
• Alternatively, download the .ics file here for use with any calendar application or service that supports the iCal format.

Join us in shaping the future of Cortex, and let's build something amazing together!

Further reading

Talks

• Apr 2025 KubeCon talk "Cortex: Insights, Updates and Roadmap" (video, slides)
• Apr 2025 KubeCon talk "Taming 50 Billion Time Series: Operating Global-Scale Prometheus Deployments on Kubernetes" (video, slides)
• Nov 2024 KubeCon talk "Cortex Intro: Multi-Tenant Scalable Prometheus" (video, slides)
• Mar 2024 KubeCon talk "Cortex Intro: Multi-Tenant Scalable Prometheus" (video, slides)
• Apr 2023 KubeCon talk "How to Run a Rock Solid Multi-Tenant Prometheus" (video, slides)
• Oct 2022 KubeCon talk "Current State and the Future of Cortex" (video, slides)
• Oct 2021 KubeCon talk "Cortex: Intro and Production Tips" (video, slides)
• Sep 2020 KubeCon talk "Scaling Prometheus: How We Got Some Thanos Into Cortex" (video, slides)
• Jul 2020 PromCon talk "Sharing is Caring: Leveraging Open Source to Improve Cortex & Thanos" (video, slides)
• Nov 2019 KubeCon talks "Cortex 101: Horizontally Scalable Long Term Storage for Prometheus" (video, slides), "Configuring Cortex for Max Performance" (video, slides, write up) and "Blazin' Fast PromQL" (slides, video, write up)
• Nov 2019 PromCon talk "Two Households, Both Alike in Dignity: Cortex and Thanos" (video, slides, write up)
• May 2019 KubeCon talks; "Cortex: Intro" (video, slides, blog post) and "Cortex: Deep Dive" (video, slides)
• Nov 2018 CloudNative London meetup talk; "Cortex: Horizontally Scalable, Highly Available Prometheus" (slides)
• Aug 2018 PromCon panel; "[Prometheus Long-Term Storage Approaches][promcon-2018-panel]" ([video][promcon-2018-video])
• Dec 2018 KubeCon talk; "Cortex: Infinitely Scalable Prometheus" (video, slides)
• Aug 2017 PromCon talk; "[Cortex: Prometheus as a Service, One Year On][promcon-2017-talk]" ([video][promcon-2017-video], [slides][promcon-2017-slides], write up [part 1][promcon-2017-writeup-1], [part 2][promcon-2017-writeup-2], [part 3][promcon-2017-writeup-3])
• Jun 2017 Prometheus London meetup talk; "Cortex: open-source, horizontally-scalable, distributed Prometheus" ([video][prometheus-london-2017-video])
• Dec 2016 KubeCon talk; "Weave Cortex: Multi-tenant, horizontally scalable Prometheus as a Service" ([video][kubecon-2016-video], [slides][kubecon-2016-slides])
• Aug 2016 PromCon talk; "Project Frankenstein: Multitenant, Scale-Out Prometheus": ([video][promcon-2016-video], [slides][promcon-2016-slides])

Blog Posts

• Dec 2020 blog post "How AWS and Grafana Labs are scaling Cortex for the cloud"
• Oct 2020 blog post "How to switch Cortex from chunks to blocks storage (and why you won't look back)"
• Oct 2020 blog post "Now GA: Cortex blocks storage for running Prometheus at scale with reduced operational complexity"
• Sep 2020 blog post "A Tale of Tail Latencies"
• Aug 2020 blog post "Scaling Prometheus: How we're pushing Cortex blocks storage to its limit and beyond"
• Jul 2020 blog post "How blocks storage in Cortex reduces operational complexity for running Prometheus at massive scale"
• Mar 2020 blog post "Cortex: Zone Aware Replication"
• Mar 2020 blog post "How we're using gossip to improve Cortex and Loki availability"
• Jan 2020 blog post "The Future of Cortex: Into the Next Decade"
• Feb 2019 blog post & podcast; "Prometheus Scalability with Bryan Boreham" (podcast)
• Feb 2019 blog post; "How Aspen Mesh Runs Cortex in Production"
• Dec 2018 CNCF blog post; "Cortex: a multi-tenant, horizontally scalable Prometheus-as-a-Service"
• Nov 2018 CNCF TOC Presentation; "Horizontally Scalable, Multi-tenant Prometheus" (slides)
• Sept 2018 blog post; "What is Cortex?"
• Jul 2018 design doc; "[Cortex Query Optimisations][cortex-query-optimisation-2018]"
• Jun 2016 design document; "Project Frankenstein: A Multi Tenant, Scale Out Prometheus"