OpenTelemetry vs Prometheus
OpenTelemetry and Prometheus are two powerful observability tools, each with its own strengths. OpenTelemetry provides a standardized way to collect, instrument, and export telemetry data. Prometheus, on the other hand, excels at time-series monitoring and alerting.
In this blog post, we will explore the similarities and differences between OpenTelemetry and Prometheus, and discuss the benefits and advantages of each.
What is OpenTelemetry?
OpenTelemetry aims to provide a unified set of APIs, libraries, agents, and instrumentation to capture distributed traces, metrics, and logs from applications. The primary goal is to standardize the collection of telemetry data across different systems and services in a cloud-native environment.
OpenTelemetry supports distributed traces, metrics and logs. It allows developers to instrument their code using APIs and SDKs to collect telemetry data, which can then be sent to various backends for analysis and visualization.
What is Prometheus?
Prometheus is an open source monitoring and alerting toolkit specifically designed to collect and store time-series metrics. Prometheus excels at monitoring individual services and infrastructure components.
Prometheus focuses on metrics collection. Prometheus uses a pull-based model where it scrapes metrics from configured targets (e.g. applications, services, exporters) at regular intervals.
OpenTelemetry advantages
Support for multiple signal types. OpenTelemetry supports capturing traces, logs, and metrics, while Prometheus is primarily a metrics monitoring tool. This means that OpenTelemetry provides a more complete view of your system's performance.
Vendor agnostic. OpenTelemetry is vendor-agnostic, meaning it can be used with a wide variety of observability backends, including open source tools such as Jaeger and Prometheus, as well as commercial offerings. This makes it more flexible and adaptable to different environments.
Future proof. OpenTelemetry is backed by the Cloud Native Computing Foundation (CNCF) and has gained significant industry support. It is considered the standard for instrumentation and observability in cloud-native environments. By adopting OpenTelemetry, you ensure that your monitoring solution is aligned with industry standards and will continue to evolve and improve over time.
Prometheus advantages
Reliability. Prometheus has a reputation for reliability and efficiency. It is used by many large enterprises to monitor their applications and infrastructure. It uses a time-series database to store metrics data, ensuring that the data is readily available when needed.
Real-time monitoring and alerting. Prometheus provides real-time monitoring and alerting capabilities that enable organizations to quickly respond to any issues. It can track the health of systems, identify potential problems, and trigger alerts based on predefined rules.
Integration with Kubernetes. Prometheus is the de facto standard monitoring solution for Kubernetes. Most third-party applications are already instrumented for Prometheus metrics, making it easy to integrate and monitor applications running on Kubernetes clusters.
Grafana integration. Prometheus seamlessly integrates with Grafana, a popular open source visualization tool. Grafana provides rich and customizable dashboards for visualizing Prometheus metrics, allowing users to create insightful and real-time visual representations of their data.
How to choose?
OpenTelemetry provides a holistic view of the performance of the entire distributed system by capturing traces and context propagation across services, allowing developers to understand end-to-end request flows.
OpenTelemetry is ideal for understanding distributed systems, troubleshooting latency issues, monitoring microservices, and gaining insight into complex service interactions.
Prometheus excels at monitoring individual components over time, making it ideal for alerting, capacity planning, and resource utilization analysis.
Prometheus is well suited for monitoring individual services, network devices, server resources, and any components that emit time-series metrics.
Using Prometheus and OpenTelemetry together
Promethes and OpenTelemetry have different data formats, but they can be integrated to work together. Using OpenTelemetry Collector, Prometheus metrics can be converted to OpenTelemetry metrics and exported to OpenTelemetry backends like Uptrace.
Uptrace is an open source APM for OpenTelemetry with an intuitive query builder, rich dashboards, automatic alerts, and integrations for most languages and frameworks. You can use it as a Prometheus-compatible backend with Grafana.
OpenTelemetry Collector is a proxy between your application and a backend that receives telemetry data, transforms it, and exports the data to various observability platforms, storage systems, or other destinations.
You can use OpenTelemetry Collector Prometheus receiver to collect Prometheus metrics:
receivers:
prometheus_simple:
collection_interval: 10s
endpoint: '172.17.0.5:9153'
metrics_path: '/metrics'
use_service_account: false
tls:
ca_file: '/path/to/ca'
cert_file: '/path/to/cert'
key_file: '/path/to/key'
insecure_skip_verify: true
You can then export the metrics to Uptrace using OpenTelemetry protocol. See Ingesting Prometheus metrics into Uptrace for details.
Conclusion
While OpenTelemetry offers certain advantages, it's worth noting that Prometheus is still a valuable tool, especially if you need to monitor individual services and infrastructure components over time.
OpenTelemetry and Prometheus are often used together. OpenTelemetry can be used to collect telemetry data from various services and then export the metrics to a system like Prometheus for monitoring, alerting, and long-term storage. This combination provides a powerful and comprehensive observability solution for modern applications.