PerfView is a CPU and memory performance-analysis tool
Macro(s) for vectorizing loops
RSpec for Rails 5+
Clinic.js diagnoses your Node.js performance issues
Scriptable database and system performance benchmark
Command Line profiler of CPU usage
Fast, full-stack, headless browser testing using node.js
An online request replication tool, also a tcp stream replay tool
Library tools to collect timing in Java, C, C++
SarBox helps user to parse or analyze sar data
A Portable Thin Client & Server Pair for XA / 2PC Testing