Distributed tracing monitors and analyzes requests as they propagate through complex systems. In distributed environments, workflows involve multiple services, each producing logs and metrics independently. Distributed tracing unifies these data streams, providing a view of the system’s performance.
By linking and visualizing individual service calls, it simplifies identifying bottlenecks, errors, or latency within the system. Tracing works by assigning a unique identifier to a request, which is then passed along through each service and operation the request interacts with.
This identifier helps in mapping the entire path a request takes across distributed services, which is referred to as a “trace.” Each segment of a trace is known as a “span,” representing a single operation. The aggregation of traces and spans provides insights into the flow and timing of requests, aiding in performance optimization and problem diagnosis.
This is part of a series of articles about observability.
Tracing mechanisms have evolved in tandem with IT architectures, moving from monoliths to microservices. In traditional monolithic architectures, tracing focused on a single, unified application where internal call paths were relatively straightforward. However, with the shift to microservices architectures, the communication between services became a complex web, each service operating in isolation.
Microservices architectures require tracing techniques that can account for distributed operations. Tracing solutions evolved by adopting context propagation methods and using visualization tools to manage complexity. This enables monitoring that aligns with the dynamic and ephemeral nature of microservices.
Learn more in our detailed guide to distributed tracing in microservices
Organizations and development teams should be familiar with the following concepts when monitoring distributed environments.
Traces are end-to-end paths that detail how requests move through a distributed system. Each trace is composed of spans, which represent individual units of work carried out by services. Together, traces and spans outline the exact path and the sequence of operations involved.
Context propagation is essential in maintaining the relationship between these spans across distributed services. It ensures that context information, like trace IDs, are consistently and accurately passed along between different components and services to create a snapshot of the request.
Each span contains metadata such as operation name, start, and end timestamps, providing insights into the performance of each service. Proper context propagation leverages headers or metadata in protocol communications, enabling trace linking between disparate systems.
Instrumentation is the process of adding tracing logic into your applications and services. It allows data to be collected on how requests are processed by different components. There are two primary techniques: manual instrumentation and automatic instrumentation.
Manual instrumentation involves adding specific trace code to individual components, providing control over the traces. Automatic instrumentation uses libraries and tools that wrap existing code to provide tracing capability, minimizing developer effort and reducing chances of missing important spans.
Effective instrumentation captures essential data without burdening the system. Choosing the right technique depends on the application’s architecture and requirements. While manual instrumentation offers control, automatic techniques support rapid deployment and consistency across diverse environments.
Trace data collection involves capturing span data emitted by instruments as requests traverse various services. This data is aggregated using centralized services that process and format the data for analysis, often employing agents or collectors spread throughout the system. Trace storage is crucial, as it maintains the history of traces for reference and inspection.
Effective storage solutions must accommodate high throughput and minimal latency to sustain real-time analysis. They should also ensure scalability to handle peak loads and surges in service usage. Common storage backends for trace data include distributed databases and cloud-native solutions that offer flexible storage capabilities.
Distributed tracing involves instrumenting each service in a system to capture trace data as requests move through the architecture. The process typically involves the following key steps:
Distributed tracing offers the following pros for monitoring, debugging, and optimizing distributed systems:
However, distributed tracing also has some drawbacks:
When implementing distributed tracing, organizations should consider the following practices to ensure optimal visibility.
Standardizing trace context across all services ensures consistency in trace data, promoting accurate trace reconstruction and analysis. By adopting universal standards for trace IDs and propagation, such as those provided by OpenTelemetry, teams can maintain coherent trace datasets even as services evolve or scale.
This standardization simplifies the instrumentation process and ensures interaction between components, especially when dealing with third-party integrations or diverse technology stacks. Careful implementation of context standards helps in achieving meaningful, actionable insights from distributed tracing efforts.
Automating instrumentation of code reduces manual errors and ensures visibility across services. Using automated tools and libraries for tracing decreases development effort, enabling consistent application of tracing logic throughout application stacks. Automated instrumentation can quickly cover a larger array of services without exhaustive manual coding.
While automation offers advantages, it is essential to monitor and adjust automated processes, ensuring they meet observability goals without unnecessary resource expenditure. Balancing automation with strategic manual instrumentation combines breadth with depth.
Optimizing sampling rates ensures critical data is gathered without overwhelming storage systems. The ideal sampling strategies capture enough trace data to provide insights while avoiding excess cost and computing resource strain. Dynamic sampling can adjust rates in real time, responding adaptively to application load or changes in traffic patterns.
Organizations must continually reevaluate sampling configurations based on system updates and performance goals. Effective sampling optimization harmonizes the need for tracing data, mitigating unnecessary data accumulation while providing reliable, actionable insights.
Integrating distributed tracing with established observability tools broadens the scope of actionable insights, combining traces with logs, metrics, and alerts to create a monitoring ecosystem. Observability platforms offer dashboards, visualizations, and analytics capabilities essential for correlating trace data with operational performance and identifying potential issues.
Interconnected observability solutions allow for unified analysis and easier performance management, linking trace data directly to actionable insights. The resulting view supports proactive system maintenance, optimizing operations across complex environments.
Regular analysis of trace data is crucial to making informed decisions and enhancing system performance. Routine review of traces helps identify trends, detect anomalies, and confirm that trace solutions provide expected value. Acting on insights derived from analyses drives continuous improvement, ensuring services remain efficient under evolving conditions.
Empirical data from traces guides strategic initiatives like capacity planning, architectural adjustments, or targeted optimizations. Continuous monitoring and refinement of trace activities ensure that the tracing technology adapts alongside applications.
Coralogix sets itself apart in observability with its modern architecture, enabling real-time insights into logs, metrics, and traces with built-in cost optimization. Coralogix’s straightforward pricing covers all its platform offerings including APM, RUM, SIEM, infrastructure monitoring and much more. With unparalleled support that features less than 1 minute response times and 1 hour resolution times, Coralogix is a leading choice for thousands of organizations across the globe.