simprof

A simple code profiler.

Basic usage

const Profiler = require('simprof');

Profiler.enable();
const profiler = new Profiler('Foo');

let prof = profiler.begin('bar');
// ...
// Do stuff
// ...
prof.end();

Getting the results

To get a dump of the profiler results, send SIGUSR2 to the relevant node process:

kill -s USR2 31337

Note that the profiler starts disabled. In addition to explicitly enabling it with Profiler.enable(), it will be enabled by sending the USR2 signal to it.

This means that you can get a dump from a disabled profiler by sending the process USR2 twice.

Advanced usage

const Profiler = require('simprof');

// Create a new profiler instance, often one per file.
const profiler = new Profiler('Whatever');

class Whatever {

	vanilla() {
		// Create a named profiler block
		// NOTE: There is no magic syntax here,
		// `#vanilla` is just a common way to refer to an instance method.
		let prof = profiler.begin('#vanilla');

		// DO ALL THE THINGS
		this.do();
		all();
		the();
		this.things();

		// End the profiler block
		prof.end();
	}

	nested() {
		// You can have nested profiler blocks,
		// which is helpful for HUGE MONOLITHIC FUNCTIONS and whatnot.
		// NOTE: Again, no magic syntax here, just human-readable names.
		let prof = profiler.begin('#nested');

		let profFoo = profiler.begin('#nested foo');
		let foo = this.foo();
		foo.blah();
		profFoo.end();

		let profBar = profiler.begin('#nested bar');
		let bar = this.bar();
		bar.blah();
		profBar.end();

		let profBaz = profiler.begin('#nested baz');
		let baz = this.baz();
		baz.blah();
		profBaz.end();

		prof.end();
	}

	async wrapAndRun() {
		// This wraps and immediately runs the given function
		return await profiler.run('#wrapAndRun()', async() => {
			// Do stuff
		});
	}

	profileSequenceOfSteps() {
		// This allows a sequence of steps within an overall function to be individually profiled
		let profseq = profiler.sequence('#profileSequenceOfSteps');
		profseq.step('step1');
		// do stuff
		profseq.step('step2');
		// do stuff
		profseq.step('step3');
		// do stuff
		profseq.end();
	}

}