Profile Node.js Apps Effortlessly: pprof to the Rescue

Your application will need to be using Node.js 14 or greater. This package is tested against current versions of Node.js: 14, 16, 18, and 20.

The pprof module has a native component that is used to collect profiles with v8's CPU and Heap profilers. You may need to install additional dependencies to build this module.

For Linux: pprof has prebuilt binaries available for Linux and Alpine Linux for Node 14 and 16. No additional dependencies are required.
For other environments: when using @google-cloud/profiler on environments that pprof does not have prebuilt binaries for, the module node-gyp will be used to build binaries. See node-gyp's documentation for information on dependencies required to build binaries with node-gyp.

The pprof CLI can be used to view profiles collected with this module. Instructions for installing the pprof CLI can be found here.

Basic Set-up

Install pprof with npm or add to your package.json.

# Install through npm while saving to the local 'package.json'
npm install --save pprof

Using the Profiler

Collect a Wall Time Profile

In code:

Update code to collect and save a profile:

View the profile with command line pprof:

Requiring from the command line

Start program from the command line:

A wall time profile for the job will be saved in pprof-profile-${process.pid}.pb.gz. View the profile with command line pprof:

Collect a Heap Profile

Enable heap profiling at the start of the application:

Collect heap profiles:

Collecting and saving a profile in profile.proto format:

View the profile with command line pprof.

Collecting a heap profile with V8 allocation profile format:

  const profile = await pprof.heap.v8Profile();

pprof -http=: heap.pb.gz

const profile = await pprof.heap.profile();
const buf = await pprof.encode(profile);
fs.writeFile('heap.pb.gz', buf, (err) => {
  if (err) throw err;
})

// The average number of bytes between samples.
const intervalBytes = 512 * 1024;

// The maximum stack depth for samples collected.
const stackDepth = 64;

heap.start(intervalBytes, stackDepth);

pprof -http=: pprof-profile-${process.pid}.pb.gz

node --require pprof app.js

pprof -http=: wall.pb.gz

const profile = await pprof.time.profile({
  durationMillis: 10000,    // time in milliseconds for which to 
                            // collect profile.
});
const buf = await pprof.encode(profile);
fs.writeFile('wall.pb.gz', buf, (err) => {
  if (err) throw err;
});

Download Details:

Author: google

Official Github: https://github.com/google/pprof-nodejs

License: Apache-2.0 license

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