V8 CPU Profiler

Use Node’s built-in V8 sampling profiler.

Detailed Description

The V8 profiler samples JavaScript execution and reports where CPU time is spent. It is built into Node, so it is useful when you cannot install extra profiling tools.

The processed output separates JavaScript, C++, and shared libraries. Start with JavaScript frames from your application code because those are usually the easiest to optimize.

Mental Model

node --prof app.js
-> generate isolate log
-> node --prof-process

When To Use

->You need zero-dependency CPU profiling
->You want a quick local profile
->Clinic is not available in the environment

Tools: node --prof, --prof-process, chrome://inspect

v8-prof.sh

Live Editor

Output

Run code to see output...