Latency

Latency is the delay between a request being made and the response being received. It is typically measured in milliseconds and is a key indicator of perceived application responsiveness.

Sources of latency include network round-trip time, database query time, I/O wait, and processing overhead. Reducing latency involves techniques such as caching, connection pooling, query optimization, and co-locating services.

Documentation

Related : Quality of Service (QoS), Performance, Benchmarking, Cache, Database, Network, Real Time, Micro-optimisation