Application performance metrics are important to decipher the extent to which an application actually helps the business it supports and reveal where improvements are needed. The key to success is to track the right metrics for your app.
These application performance metrics, commonly known as key performance indicators (KPIs), are a quantitative measure of how effectively the organization achieves the business objectives. Capturing the right metrics will give you a comprehensive report and powerful insights into ways to improve your application.
Below are five core application performance metrics that developers should track.
1. CPU usage
CPU usage affects the responsiveness of an application. High spikes in CPU usage may indicate several problems. Specifically, this suggests the application is busy spending time on computing, causing the responsiveness of an application to degrade. High spikes in usage should be considered a performance bug, since it means the CPU has reached its usage threshold.
2. Memory usage
Memory usage is also an important application performance metric. High memory usage indicates high resource consumption in the server. When tracking an application's memory usage, keep an eye on the number of page faults, and disk access times. If you have allocated inadequate virtual memory, then your application is spending more time on thrashing than anything else.
3. Requests per minute and bytes per request
Tracking the number of requests your application's API receives per minute can help determine how the server performs under different loads. It is equally important to track the amount of data the application handles during every request. You may find that the application receives more requests than it can manage, or that the amount of data it is forced to handle is hurting performance.
4. Latency and uptime
Latency (usually measured in milliseconds) refers to the delay between a user's action on an application and the response of the application to that action. Higher latency has a direct impact on the load time of an application. You should take advantage of a ping service to test uptime. These services can be configured to run at specific intervals of time to determine whether an application is up and running.
KPIs for APIs
API analysis and reporting are important aspects of app development, and APIs have their own set of KPIs that development teams need to track.
Some of the most important KPIs for APIs to pay attention to include:
- Usage count. The number of times an API call is made over a certain period of time.
- Request latency. The amount of time it takes for an API to process incoming requests.
- Request size. The size of incoming request payloads.
- Response size. The size of outgoing response payloads.
5. Security exposure
You should ensure that both your application and data are safe. Determine how much of the application is covered by security techniques, and how much is exposed and unsecure. You should also have a plan in place to determine how much time it takes -- or may take -- to resolve certain security vulnerabilities.