Node.js server monitoring

Node.js Server Monitoring: A How to Guide

Christoph Leitner Developer Tips, Tricks & Resources

Node.js is one of the most popular Javascript frameworks in 2021. With the increasing demand for Node.js comes the crucial next step of Node.js server monitoring. 

The best way to monitor your Node.js server is with an Application Performance Monitoring (APM) tool. 

Keep in mind, Node.js server monitoring is a bit of a tricky task, and there are particular challenges you should be aware of. But don’t worry because this how-to guide will walk you through it step-by-step. 


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What is Node.js Server Monitoring, and Why Is It Important To Use an APM?

First, let’s quickly review what exactly Node.js monitoring is.

Monitoring your Node.js server means you are making sure it’s performing optimally and nothing is blocking the thread or event queue. 

If it’s not running correctly, customers will get a  loading screen, and they will undoubtedly be turned off by an error message. Unfortunately–once customers lose trust in you–it’s hard to get them back.

The cost of unplanned server downtime is between $5,600-$9,000 per minute. That’s more than half a million dollars lost for every hour that your server is offline! 

You will want to install an APM tool to mitigate any disaster–even the disasters you cannot see (bad code can go unnoticed for an extended period of time). 

APM systems are extremely helpful because they pinpoint the problem in the code so you can fix it quickly. Long term, you will not regret it. If you catch small problems early, they won’t turn into big problems later. 

Factors to Monitor

So we’ve established why you need to invest in an APM system, but what are you monitoring with it? Essentially, you are monitoring server health and resource utilization (poorly-optimized applications use more resources, cost you more money, and are slow). Let’s get into the nitty- gritty, shall we? 

Specific things you should evaluate include:

  • CPU usage –  how much the processor is working
  • Average response time – the amount of time the server takes to return the results of a request
  • Bandwidth –  the maximum rate of data transfer 
  • Garbage collection –  automatic memory management
  • Memory usage and leaks – a useless block of memory that results in crashes and slowdowns 
  • Event loop – allows Node.js to perform non-blocking I/O operations

The Best Node.js Server Monitoring Tools

Node js has a wide scope of functionality and so as you might have expected, there are quite a few Node.js monitoring tools on the market, all in different shapes and sizes. So pay attention!

Retrace

Retrace is a popular cloud-based tool for APM used by organizations of all sizes. It can be used to improve the performance of your applications. Some notable features include:

  • Centralized logs
  • Error and log integration
  • Two-factor authentication
  • Single-sign-on
  • Dev-centric insights

Retrace users proactively identify more issues in QA and continuously improve and observe applications in production environments.  Retrace uses lightweight profiling to automatically track key methods in your code. Detailed performance data helps you understand how your code is performing and how to improve it. Try your free, 14 day Retrace trial.  

PM2

PM2 is another popular Node.js monitoring tool. It is a straightforward tool for those who run and monitor live production workloads from a CLI or web interface. Notable features include:

  • Daemon process manager
  • Auto-clustering
  • Container integration
  • Log management

Keep in mind, to utilize this tool, you will need to install NPM.

Express Status Monitor

Express Status Monitor is an open-tool that offers real time monitoring of Express-based node servers. 

For those who don’t know, Express.js–or simply Express–is the “de facto standard server framework for Node.js”.   

Notable features of Express Status Monitor include:

  • Monitor response time
  • Status code 
  • Request frequency
  • Memory and CPU utilization

Appmetrics

Appmetrics is a top-notch performance monitoring, open-source tool managed by IBM. Some notables features include:

  • Uses node-gyp command
  • Dash plugin for app monitoring
  • Free, open-source 
  • Data transaction
  • Network speed

Keep in mind, to use Appmetrics, you will need to get node app metrics from npmjs.org, Github, and IBM SDK for Node.js

Prometheus

Prometheus is a prominent open-source, community-powered APM developed at SoundCloud in 2012. Node.js developers can find it under the Apache 2 License on Github. Notable features include:

  • Excellent visualization
  • Precise alerting
  • Many integrations
  • Many client libraries
  • Efficient storage

If Prometheus interests you as it does many people, read more about it in Prometheus: Up & Running: Infrastructure and Application Performance Monitoring.

Handling Errors

If you want your server to be bug-free and performative, you have to handle the errors or at least know what they look like. Below are the errors you may come across while monitoring your server. 

  1. Error Object and Error Types

There are multiple types of error including:

  • EvalError
  • RangeError
  • ReferenceError
  • SyntaxError
  • TypeError
  • URIError
  • AggregateError
  • InternalError
  1. Try…Catch
  1. Throw
  1. Call Stack
  1. Effective Function Naming
  1. Asynchronous Paradigms Like Promise

Promise comes in a few states:

  • Pending – initial state, neither fulfilled nor rejected.
  • Fulfilled – meaning that the operation was completed successfully.
  • Rejected – meaning that the operation failed.

Granted, handling these errors is a daunting task.This best practices guide can further aid you.

Why Do Server Crashes Happen and Can You Prevent Them?

Server crashes happen for two main reasons. The first one is poor maintenance, which you can control– fix the incorrectly formatted plugins or internal coding errors. If you do not fix them right away, they could hurt you long term by causing a crash.

The second is external factors, which you have less control over. By external factors, I am referring to viruses, hackers, and traffic overload.

According to IBM, the average cost of a data breach is just shy of $4 million dollars. In today’s day and age, servers store a ton of data and for hackers, data equals dollar signs. Therefore, the safety and security of your server data is of the utmost importance. 

In conclusion, it is important to monitor your Node.js server so you can find bottlenecks fast and mitigate them before too many customers turn away. Using an APM system is the best way to monitor your server. It finds the performance issues for you and supplies you with an easy way of solving them. 
Now that you know more about Node js Monitoring, what’s your next lesson in Node.js? Check out this Node js Web Scraping Tutorial.