Observability Part1— Demystifying MELT Telemetry Data: Metrics, Events, Logs, Traces
To have a better observability in our system, the first step is to gather performance data. In this article, we will try to understand the four key telemetry data types which we rely on to gain insights into system performance. The acronym that encapsulates these data types is MELT, which stands for Metrics, Events, Logs, and Traces. We will explore each of these telemetry data types using a flight reservation system as an example.
Metrics
Metrics are aggregated numbers calculated by observing events over a period of time. They provide us a high-level summary of what is happening in our system. Think of metrics as the big picture view.
In our flight reservation system example, a metric could be the average booking time for flights over the last hour. This metric is calculated by observing the start and end times of flight bookings during that time period.
Events
Events are distinct actions occurring at a specific moment in time. They capture discrete occurrences in our system. An event contains information such as a timestamp and relevant details about the action.