Access the V8 profiler from node.js
Access the V8 profiler from node.js - http://nodejs.org/
This module is effectively deprecated. Newer versions of V8 have removed much of the functionality that node-profiler depends on. As a result, it's become much less effective.
Consider using strong-agent if you want on-demand CPU profiling.
This module is for people who need fine-grained run-time control over the V8
profiler. You don't need it if all you want is wholesale profiling, simply
node with profiling enabled:
node --prof application.js
Read on, however, if you want to wield the arcane powers this module grants.
Easy as pie. To build from source:
node-gyp configure build install
Or, if you have
npm install profiler
In most cases you will want to start your application with the profiler in suspended animation.
node --prof --prof_lazy --log application.js
And inside your application:
var profiler = require('profiler'); // // <here be code you don't want to profile> // profiler.resume(); // // <performance critical code here> // profiler.pause();
This results in a v8.log being written to the current directory that you can
process with the bundled
nprof tool. Run
sh tools/build-nprof to build it.
You will sometimes want to run the garbage collector before profiling a performance critical section of code. Here is how you do it:
$ cat application.js if (typeof gc === 'function') gc(); profiler.resume(); // ... $ node --prof --prof_lazy --log --expose-gc application.js