P99
In plain terms
The 99th-percentile value, capturing near-worst-case behavior.
Going deeper
P99 is the value below which 99% of measurements fall, highlighting the slowest 1% of requests that affect user experience. It exposes tail latency.
Under the hood
Critical for SLOs since a few slow requests hurt users; averages can hide bad tails.
Examples
Tail latency, SLOs, performance monitoring, worst-case analysis, alerts.
Think of it like...
Like measuring how bad your slowest 1 in 100 trips is, not just the typical one.