Microservice Application Monitoring Tips and Tricks

Special contributor to Scout APM  on August 31, 2022

Microservices have grown to become one of the most optimal alternatives to monoliths. However, just building your app and releasing it to the public isn’t everything. Monitoring microservices is as important as building and releasing them.

You need to maintain it to resolve issues that may occur and also introduce new features from time to time. Doing these without an active monitoring setup is similar to shooting arrows in the dark; you are putting in the required effort, but you don’t know if you’re hitting the target. You might as well be shooting in the wrong direction altogether.

In this guide, you will learn why monitoring microservices is important and some tips you can use to get a head start on your microservices monitoring efforts.

Feel free to use these links to navigate the guide:

Without further ado, let’s begin!

Why is Monitoring Microservices Important?

Before we move on to show you how you can do microservices monitoring right, let’s try to understand why you should do it all.

Provide a Great Experience to Your Users

One of the best reasons to implement any form of monitoring in your apps is that it helps you provide a better experience for your users. If you are unaware of what your users see when they try to use your app, you will never be able to understand why they ultimately gave up and left your product.

Even if you put downtimes and bugs aside, many performance issues restrict your app from performing at its full potential. While a delay of 300-400 ms might be passable for your users when performing a transaction in your app, bringing it down to 50-100 ms will surely make it more convenient and smooth for them. In complex systems like microservices, downtimes usually aren’t as frequent as performance bottlenecks, so there’s plenty of room for you to improve your user experience by making small tweaks and fixing bottlenecks.

Meet Your SLAs

Apart from promising your users a great experience, you also agree to provide a certain standard of quality when signing up customers. These standards are defined in an agreement called Service Level Agreements (SLAs). SLAs lay out the metrics, expectations, and responsibilities that may be used to determine if the vendor, that is you, delivered what you promised. 

Examples can include 99.99 percent network availability, a response time of fewer than 10 minutes to downtime, etc. Breaching SLAs can result in penalties, including monetary compensation to your customers. The right monitoring services enable you to align your microservices-based app’s metrics with those outlined in your SLAs and alert you when there is a chance or prediction of a breach.

Fix Problems and Reduce Downtimes

If you keep customer satisfaction and legalities like SLAs aside for a while, you still need to ensure that your app keeps running and enables its users to get their work done. Monitoring microservices is essential for apps of all scales. Even if you have just started out and are not developed enough to invest in SLAs or prioritize user experience, you still need your app to run as expected for you to understand how it is received by your users and how you can make it better.

Without implementing monitoring measures that track downtimes and help you keep your application up all the time, it does not make any sense to release and maintain an app in public.

Identify Patterns and Prevent Downtimes 

For apps that have just started to gain some traction, simply reducing downtimes is not enough. You need to proactively look out for areas that might turn into a source of downtimes in the future. Monitoring microservices can help you achieve that as many microservices monitoring tools enable you to log historical data and run predictive analysis on them to identify usage and resource consumption patterns. You can then rely on these patterns to know when a particular component may run out of resources or go down due to another issue.

If you are only responding to downtimes by tracking when they occur and releasing fixes to resolve them, you will never be able to achieve a healthy system that goes down less often. This is because you will keep reacting to the symptoms and not the cause itself. This is called a reactive approach, and it is usually helpful only during the initial development phase when issue resolution is not a priority.

You need to switch to a proactive approach in which you not only release fixes for issues you also investigate why they occurred, whether they were part of a long-running pattern, and whether they could have been identified before they caused a downtime. Microservices monitoring can help you do all this.

Key Tips and Tricks

Now that you understand why monitoring microservices is important, let’s take a look at some of the key tips and tricks that can help you get the most out of your microservices monitoring efforts.

Pick a Few Systems to Test

One of the most important things to keep in mind when monitoring microservices is to identify a set of systems of components that you are going to focus on. If you choose a large number of systems in the beginning, you will have to put in extra effort to receive good results. On the other hand, if your target group is too small, you will be wasting too much effort on a few components.

Start with a moderately-sized group of key components from your app. You can always revisit the components once your microservices monitoring strategy starts to show effects.

Choose Metrics Carefully

Once you have the right set of systems selected, the next step is to choose the correct metrics. While there are a near-endless number of metrics that you can track in most microservices-based systems, not all of them are going to give you the same results. There are three different types of metrics involved in most microservices-based apps. Here’s how you can pick out the perfect set for each type:

Application Metrics

Application metrics are specific to the business logic of your app. They can be anything from successful user registrations per minute to the number of active users in the app at any given moment. However, not all metrics apply to all types of apps. You need to ensure that the metrics are relevant to your app’s growth. For instance, tracking the number of active users in an ecommerce app might not be as relevant as it would to a multiplayer game. 

Platform Metrics

These metrics are derived from the underlying platform of your app and are usually the same for most kinds of applications. Some of the common platform metrics to track are:

These metrics help you understand the internal functioning of your apps. They can alert you when the response time or bandwidth for an endpoint or a service decreases so that you can take action before they go completely dead.

System Events

Finally, you need to keep an eye on how the events that occur across the system affect the performance of your microservices-based app. Here are a few key system events that you should consider tracking:

More often than not, these events are related to downtimes or performance drops. While it can be difficult to generate metrics on all of these, often logging these events in your performance data store can be enough to correlate their effects with your app’s state.

Accompany Work with APM Software

Monitoring microservices without a proactive APM software like Scout doesn’t make much sense. APM tools provide you with ready-to-use instrumentation, quick dashboards, and powerful analytics on your performance data. If you are looking to build and grow a microservices-based app, opting for APM software is a no-brainer.

Instrument Metrics at Extension Points

Extension points are often used to extend application functionality without altering the code of the app. On the server side, they can be as simple as a script plugged into your app dynamically to add some small features. On the front end, they can be UI macros like HTML extensions that can be used to add custom content to a webpage without altering its source code manually.

It is important that you instrument the code that gets plugged in via extension points so that you monitor their impact on the performance of your app as well. More often than not, extension points cause issues due to a lack of quality control and active monitoring over their code.

Tracing logs

While logs are a good way of understanding what happened with a component at a given time, they might not provide you insight into the complete picture of your app. Especially when your app is distributed across multiple microservices, you should consider implementing tracing. Tracing helps you understand and draw a complete picture of how various events occurred across multiple components. 

For microservices, distributed tracing can help you track requests as they move through your microservices-based app and identify sources of performance issues or bottlenecks.

Difference between Monolithic Application Monitoring vs. Microservices Monitoring

Monolith applications are those that house all of their components in the same system. Unlike microservices, there is tight coupling in the app, and often, only a single executable is deployed for delivering the app to the users.

Monitoring a microservices-based app is very different from monitoring a monolith app. While the modularity of microservices helps with scaling and lifecycle management, it makes it difficult to track what’s happening inside the app.

Monitoring microservices often requires implementing a complex setup for tracing requests as they travel through various components. For monolithic apps, everything happens inside one system, so instrumenting the app and collating performance data is simpler.

Also, a microservices-based app relies heavily on its internal network for all the components to work well together. On the other hand, monoliths do not need any network dependencies because all of their components are housed in the same system. This frees you from monitoring the network of your app and helps you focus on instrumenting your business logic well.

However, it is important to note that a difficult setup process does not equal bad results. If you are able to bear the tricky process of setting up a monitoring solution for your microservices-based app, you are set to receive all the benefits discussed in this guide. Also, this in no way downplays the advantages of microservices over traditional monoliths; it simply means you need to put in more effort to get better results.

Conclusion

The microservices architecture is on the rise thanks to its high scalability and fault tolerance. It offers numerous benefits over traditional monolithic architecture, and a lot of companies have started to offer tools that make your life easy while building microservices.

However, monitoring remains a rather tricky part of the microservices equation. In this guide, we looked at some of the benefits of implementing monitoring in your microservices-based app. We discussed its importance and shared a few key tips and tricks to help you get the most out of it.We hope that this guide motivates you to try out microservices monitoring in your project. Scout offers a premier microservices monitoring tool, and you can check out our features by signing up for a 14-day free trial!