Glossary of Terms

Application Performance Monitoring (APM)

What is Application Performance Monitoring (APM)?

Application Performance Monitoring (APM) helps IT organizations detect and diagnose disruptions in the performance of their websites and applications. Detecting disruptions in performance allows companies to maintain high-quality web and application experiences for their users or customers.

These days, APM is a broad term and can apply to the measurement of metrics and data collection from servers, code-level performance, and network performance (like traffic). Application performance monitoring provides insight into back-end and front-end performance by tracking all components and sub-components of an application.

Requests and transactions are also monitored through the entire stack in all relevant infrastructure systems. Collected data provides insight into potential issues with the services, systems, calls, and queries.

It’s important to note that application performance management (also referred to as APM) is an umbrella term for many disciplines within the monitoring space. It’s not the same thing as application performance monitoring, although the two are often used interchangeably.

Application performance management is more of a “strategy” that application performance monitoring would fall under. You measure performance with application monitoring. But, you build and optimize application performance management strategies with data from different disciplines like monitoring, modeling, and capacity planning.

Why is APM important?

APM is vital to delivering great user experiences without compromising application performance. It gives comprehensive, real-time insight into all the pieces that make up an application or website — from the database to the web server and the systems in between, like firewalls and load balancers. What makes APM indispensable?

1. Monitoring the entire delivery chain

With web applications, tracking the uptime and downtime is not enough. Every component in the service delivery chain is susceptible to performance issues — from the DNS-resolution process to the page-render process. So, it’s essential to monitor transactions and other critical modules of the application to give users a seamless experience.

APM is like an overall health report of your application. Analyzing the data helps you identify bottlenecks and fix incidents faster.

2. Understanding user behavior

Active (or synthetic) monitoring helps preempt issues, giving you ample time to fix problems before they impact user experience and your business. APM should be paired with active monitoring, which simulates user behavior (with robots) across different networks and locations.

3. Optimizing network architecture

Modern applications and sites are complex networks, with many parts that must work together to keep applications running. All these working parts require constant checks as there are multiple points of vulnerability. An APM tool can give you performance data for each vulnerable point, making it easier to troubleshoot issues.

The ideal Application Performance Monitoring strategy

According to the Gartner Magic Quadrant the three primary pieces of an application performance monitoring solution are:

  1. Digital experience monitoring (DEM) to view the application from the end user’s perspective. Active and passive monitoring collect metrics that give insight into performance from the end user perspective.
  2. Application discovery, tracing, and diagnostics (ADTD) to aide with incident remediation. Understanding the relationship between servers, how a transaction is mapped across servers, and tracking the most critical parts of an application increases mean time to resolve (MTTR).
  3. Application analytics to support Java and .NET application servers. IT teams can automatically detect performance anomalies with machine learning, interference, and other modeling methods.

APM metrics and data

Application performance monitoring solutions gather metrics through agents installed on all hosts within a given infrastructure. Because APM can collect data at code-level, specific implementations are required for different coding languages.

APM collects these metrics from different parts of infrastructure:

  • CPU and memory utilization.
  • Error rates.
  • Latency and response times.
  • Network utilization.
  • Requests and transactions per second.

The metrics highlight these issues:

  • Memory leaks.
  • Code-level inefficiencies.
  • Unoptimized database queries.
  • Performance bottlenecks.
  • Overloaded systems.

Companies can meet end user expectations and business objectives when they understand what their application is doing, how long it takes to serve requests, and how customers use their services.

The evolution of Application Performance Monitoring

The complexity of today’s IT infrastructure, which includes cloud, auto-scaling, containers, and serverless, means businesses can’t rely solely on data from traditional application performance monitoring.

Today, organizations need to auto detect whether services are in a traditional data center or in the cloud. Organizations must also automatically recognize and track all the parts that their application relies on.

APM solutions available today have overcome much of the limitations plaguing traditional tools. Application monitoring collects data not only on uptime, but can now isolate back-end/infrastructure issues, DNS issues, ISP failures, and more.

Advanced APM solutions work with other monitoring tools to provide a complete and comprehensive view of application performance.

Modern companies typically combine other monitoring solutions with application performance monitoring to improve one of three business objectives:

  • Increase revenue.
  • Improve operational efficiencies.
  • To improve brand/customer loyalty.

This extra visibility into the end user's perspective gives a company insight into:

  • Performance of third-party content.
  • Regional, network, and browser-related performance problems.
  • Protocol-specific issues.

Active monitoring combined with application performance monitoring are two elements of a comprehensive monitoring strategy. These two pieces need to work together to provide application users with the best possible experience.


Application performance monitoring is a vital component to any organization looking to provide users with a seamless experience. APM helps companies:

  • Understand and improve user experience.
  • Monitor all the parts that make up their application or website.
  • Optimize the network of parts within their infrastructure.

Modern APM works best in conjunction with other monitoring solutions, like active monitoring and digital experience observability tools.