# Performance > An index and topic collection covering API and web performance, including load testing, performance benchmarking, real user monitoring (RUM), Core Web Vitals measurement, latency profiling, distributed tracing, and application performance monitoring (APM). Performance engineering ensures that API... This is the **Performance** topic area of [API Evangelist](https://apievangelist.com) — a network of focused knowledge bases drawn from 16 years of independent API research by Kin Lane. Browse all areas at https://apievangelist.com/areas/. ## Services & Tools - [k6](https://providers.apis.io/providers/k6/) (repo: https://github.com/api-evangelist/k6) - [Apache JMeter](https://providers.apis.io/providers/apache-jmeter/) (repo: https://github.com/api-evangelist/apache-jmeter) - [Locust](https://providers.apis.io/providers/locust/) (repo: https://github.com/api-evangelist/locust) - [Gatling](https://providers.apis.io/providers/gatling/) (repo: https://github.com/api-evangelist/gatling) - [Artillery](https://providers.apis.io/providers/artillery/) (repo: https://github.com/api-evangelist/artillery) - [StormForge](https://providers.apis.io/providers/stormforge/) (repo: https://github.com/api-evangelist/stormforge) - [Speedscale](https://providers.apis.io/providers/speedscale/) (repo: https://github.com/api-evangelist/speedscale) - [GoReplay](https://providers.apis.io/providers/goreplay/) (repo: https://github.com/api-evangelist/goreplay) - [Google PageSpeed](https://providers.apis.io/providers/google-pagespeed/) (repo: https://github.com/api-evangelist/google-pagespeed) - [Pingdom](https://providers.apis.io/providers/pingdom/) (repo: https://github.com/api-evangelist/pingdom) - [Akamai](https://providers.apis.io/providers/akamai/) (repo: https://github.com/api-evangelist/akamai) - [Datadog](https://providers.apis.io/providers/datadog/) (repo: https://github.com/api-evangelist/datadog) - [New Relic](https://providers.apis.io/providers/new-relic/) (repo: https://github.com/api-evangelist/new-relic) - [Dynatrace](https://providers.apis.io/providers/dynatrace/) (repo: https://github.com/api-evangelist/dynatrace) - [AppDynamics](https://providers.apis.io/providers/appdynamics/) (repo: https://github.com/api-evangelist/appdynamics) - [Instana](https://providers.apis.io/providers/instana/) (repo: https://github.com/api-evangelist/instana) - [Sentry](https://providers.apis.io/providers/sentry/) (repo: https://github.com/api-evangelist/sentry) - [Honeycomb](https://providers.apis.io/providers/honeycomb/) (repo: https://github.com/api-evangelist/honeycomb) - [Lightstep](https://providers.apis.io/providers/lightstep/) (repo: https://github.com/api-evangelist/lightstep) - [SigNoz](https://providers.apis.io/providers/signoz/) (repo: https://github.com/api-evangelist/signoz) - [Uptrace](https://providers.apis.io/providers/uptrace/) (repo: https://github.com/api-evangelist/uptrace) - [OpenTelemetry](https://providers.apis.io/providers/opentelemetry/) (repo: https://github.com/api-evangelist/opentelemetry) - [Jaeger](https://providers.apis.io/providers/jaeger/) (repo: https://github.com/api-evangelist/jaeger) - [Grafana Tempo](https://providers.apis.io/providers/grafana-tempo/) (repo: https://github.com/api-evangelist/grafana-tempo) - [Google Cloud Profiler](https://providers.apis.io/providers/google-cloud-profiler/) (repo: https://github.com/api-evangelist/google-cloud-profiler) - [Google Cloud Trace](https://providers.apis.io/providers/google-cloud-trace/) (repo: https://github.com/api-evangelist/google-cloud-trace) - [AWS X-Ray](https://providers.apis.io/providers/aws-x-ray/) (repo: https://github.com/api-evangelist/aws-x-ray) - [Grafana](https://providers.apis.io/providers/grafana/) (repo: https://github.com/api-evangelist/grafana) ## Common Features - **Load and Stress Testing**: Open-source and managed load generators like k6, Apache JMeter, Locust, Gatling, and Artillery simulate concurrent users and traffic patterns against APIs to characterize throughput, error rate, and latency under load. - **Performance Benchmarking**: Repeatable, scripted benchmark runs establish performance baselines and detect regressions in CI/CD pipelines using tools like k6 Cloud, BlazeMeter, and StormForge. - **Real User Monitoring (RUM)**: RUM products like Akamai mPulse, Datadog RUM, New Relic Browser, Sentry Performance, and Pingdom capture latency, errors, and Core Web Vitals from real browser sessions in production. - **Synthetic Monitoring and Web Vitals**: Synthetic checks and lab-based audits from Google PageSpeed (Lighthouse), WebPageTest, and Pingdom measure Core Web Vitals (LCP, INP, CLS) and uptime from controlled environments. - **Distributed Tracing**: OpenTelemetry, Jaeger, Grafana Tempo, Honeycomb, Lightstep, Google Cloud Trace, and AWS X-Ray collect distributed traces across microservice calls to attribute latency to specific spans. - **Application Performance Monitoring (APM)**: APM platforms like Datadog APM, New Relic, Dynatrace, AppDynamics, Instana, SigNoz, and Uptrace correlate traces, metrics, and logs to surface slow transactions and code-level bottlenecks. - **Profiling and Code Hotspots**: Continuous profilers like Google Cloud Profiler and Datadog Continuous Profiler identify CPU, memory, and lock contention hotspots in running services. - **Traffic Replay and Chaos**: Tools like GoReplay and Speedscale capture production traffic and replay it against staging or new versions to validate performance and behavior before release. ## Use Cases - **Pre-Release Load Testing in CI/CD**: Engineering teams run k6 or JMeter scenarios on every pull request to verify that p95 latency and error rates stay within service-level objectives before merging. - **Core Web Vitals Optimization**: Web teams use Google PageSpeed, WebPageTest, and RUM data to optimize LCP, INP, and CLS to meet Google ranking and user-experience thresholds. - **Capacity Planning and Scalability Validation**: Platform teams use StormForge and BlazeMeter to drive sustained load tests against staging environments to determine maximum sustainable throughput and right-size infrastructure. - **Latency Regression Detection**: APM platforms like Datadog, New Relic, and Dynatrace alert on p95 and p99 latency regressions per endpoint or trace span after each deploy. - **Production Traffic Replay**: Teams use GoReplay or Speedscale to record real production traffic and replay it against release candidates to find performance and correctness regressions before rollout. - **Distributed Trace Root-Cause Analysis**: SREs use Honeycomb, Lightstep, Jaeger, or Grafana Tempo to drill into slow distributed traces and pinpoint the service, query, or downstream call responsible for tail latency. - **Continuous Profiling of Hot Paths**: Backend teams use Google Cloud Profiler or Datadog Continuous Profiler to identify CPU and memory hotspots in running services without rebuilding or redeploying. ## Related Areas - [Testing](https://testing.apievangelist.com): A curated index of services, tooling, and open source solutions for API testing, mocking, load testing, contract test... - [Observability](https://observability.apievangelist.com): A curated index of services, tooling, and open source solutions for API observability, monitoring, logging, tracing, ... - [Browsers](https://browsers.apievangelist.com): An index and topic collection covering programmable browsers, headless browser engines, and browser-automation APIs. ... - [Breaches](https://breaches.apievangelist.com): An index and topic collection covering data breach intelligence, credential exposure databases, dark-web monitoring, ... - [Monitoring](https://monitoring.apievangelist.com): An index and topic collection covering API monitoring, application performance monitoring, observability, uptime moni... - [Microservices](https://microservices.apievangelist.com): An index of microservices architecture frameworks, service discovery, resilience, messaging, workflow orchestration, ... ## More - [Latest Performance stories](/stories/) - [All API Evangelist topic areas](https://apievangelist.com/areas/) - [API Evangelist network index (llms.txt)](https://apievangelist.com/llms.txt)