APM tracks how your applications actually perform for users, latency, errors, throughput and the code behind them.
APM (Application Performance Monitoring) is the practice of measuring the performance and availability of software applications, their latency, throughput, error rate and resource use, and tracing individual requests to code, so teams can detect and diagnose issues that affect the user experience.
At its core APM watches the request-centric signals of an application: response time (latency), throughput (requests per second), and error rate, per endpoint or transaction. Beyond those, it adds depth: distributed traces that follow a request across services, database and downstream call timing, and runtime health (garbage collection, threads, memory). The point is not just to know a service is slow, but to know which request, which call, and which line of code is responsible.
Traditional APM meant a proprietary agent per language, tied to one vendor, that you installed and paid for by host. Modern APM is increasingly built on OpenTelemetry: you instrument once with an open standard, and the same traces and metrics can go to any backend. For microservices, distributed tracing has moved from a nice-to-have to the centre of APM, because a single request now crosses many services and only a trace shows where its time went.
| APM signal | What it captures |
|---|---|
| Latency | Response time per endpoint, watched as p95/p99, not averages |
| Throughput | Request rate, the load context for everything else |
| Error rate | Failed requests per endpoint, the direct measure of things going wrong |
| Traces | The path and timing of a request across services, down to the slow call |
| Runtime health | GC pauses, threads, memory, the language-runtime causes of latency |
Ops Singularity ingests APM traces and metrics over OpenTelemetry through its TelemetryOps pillar, and Sentinel AI resolves the application incidents they reveal, a slow endpoint, a failing dependency, a runtime problem, through governed, reversible Action Tickets, so APM leads to resolution, not just a dashboard.
APM is a focused kind of monitoring aimed at application performance and user experience, latency, errors, throughput and code-level detail, rather than infrastructure or logs alone.
Not anymore. Modern APM is increasingly built on OpenTelemetry, so you instrument once with an open standard and send the data to any compatible backend, avoiding lock-in.
Ops Singularity turns open telemetry into autonomous, governed resolution. See it on your own stack.