What are the Four Golden Signals and Why Do They Matter?

The Four Golden Signals are a methodology used by Site Reliability Engineers (SREs) to understand the health and performance of complex systems, particularly those using cloud services. This approach focuses on four types of observability insights: latency, traffic, errors, and saturation. Latency measures the time it takes for a request to be processed, while traffic tracks the number of successful requests. Errors measure the number of failed or unexpected responses, and saturation indicates how much resources are being consumed relative to available resources. By monitoring these signals together, SREs can identify root causes of issues, optimize system performance, and make informed decisions about resource allocation. The Four Golden Signals method is considered effective because it provides a holistic understanding of application performance and system health, allowing teams to address problems proactively and improve the overall user experience.