Sitespeed.io is an open source tool that helps you monitor, analyze and optimize your website speed and performance, based on performance best practices advices from the coach and collecting browser metrics using the Navigation Timing API, User Timings and Visual Metrics (FirstVisualChange, SpeedIndex & LastVisualChange).

High performance Java APM. Powered by ASM. Try it. Test it. If you feel its better, use it.

Collect performance metrics for your library/application.

Scouter is an open source APM (Application Performance Management) tool.

Processor Counter Monitor

Performance-Bookmarklet helps to analyze the current page through the Resource Timing API, Navigation Timing API and User-Timing - requests by type, domain, load times, marks and more. Sort of a light live WebPageTest.

Performance Metrics for Web Browsers

CoreFreq is a CPU monitoring software designed for the 64-bits Processors.

Application Layer DoS attack simulator

APM Server

Node Application Metrics provides a foundational infrastructure for collecting resource and performance monitoring data for Node.js-based applications.

.NET Standard library to instrument apps for the Prometheus metrics and monitoring system

DEPRECATED StackImpact Python Profiler - Production-Grade Performance Profiler: CPU, memory allocations, blocking calls, exceptions, metrics, and more

inspectIT is the leading Open Source APM (Application Performance Management) tool for analyzing your Java (EE) applications.

Golang application performance data monitoring.

Elastic APM Node.js Agent

This is the development repository of SparkMeasure, a tool for performance troubleshooting of Apache Spark workloads. It simplifies the collection and analysis of Spark task metrics data.

Qubole Sparklens tool for performance tuning Apache Spark

DEPRECATED StackImpact Go Profiler - Production-Grade Performance Profiler: CPU, memory allocations, blocking calls, errors, metrics, and more

Responsive, SVG based HAR waterfall viewer

🎮 더 빠르게 작동하는 프론트엔드 성능 체크리스트

DEPRECATED - See Elastic APM instead: https://github.com/elastic/apm-agent-nodejs

Elastic APM Real User Monitoring JavaScript agent

前端性能指标的监控,采集以及上报。用于测量第一个dom生成的时间(FP/FCP/LCP)、用户最早可操作时间（fid|tti）和组件的生命周期性能,，网络状况以及资源大小等等。向监控后台报告实际用户测量值。

Automatic web components profiling in chrome devtools

A tool for scale and performance testing of HDFS with a specific focus on the NameNode.

Navigation Timing

Performance Timeline