Glossary¶

Quick Lookup¶

Common terms used in this module:

• Signal - a derived metric created from raw data
• Raw Metric - a directly recorded measurement from a system
• Derived Metric - a value calculated from one or more raw metrics
• Error Rate - proportion of errors relative to total requests
• Latency - the time required for a system to respond to a request
• Throughput - the volume of work processed by a system (for example, number of requests)

Raw Metric¶

A measurement recorded directly from a system. Examples:

• number of requests
• number of errors
• total latency

Raw metrics describe what happened but may not be the easiest values to interpret.

Signal¶

A signal is a derived metric designed to make system behavior easier to understand. Signals are usually created by combining or transforming raw metrics. Examples:

• error rate
• average latency per request
• throughput

Signals help analysts monitor system health and detect unusual behavior.

Error Rate¶

The proportion of failed requests relative to total requests. This signal helps identify reliability problems in a system.

error_rate = errors / requests

Latency¶

The time required for a system to respond to a request. In this module, we often compute average latency per request:

avg_latency = total_latency_ms / requests

Throughput¶

The amount of work processed by a system in a given observation period. Examples include:

• requests handled
• transactions processed
• messages delivered

Feature Engineering¶

The process of creating new variables (features or signals) from existing data. Signal design is a form of feature engineering for monitoring systems. Feature engineering often includes:

• ratios (errors / requests)
• averages (latency per request)
• aggregations (rolling means)
• transformations (log, scaling, normalization)

Signal Design¶

The process of creating useful signals from raw system metrics. Well-designed signals make system behavior easier to monitor and interpret, which is essential for continuous intelligence systems.