Traces
Trace Tail Shift
Updated Jul 29, 2026 · today
Catches partial degradation: most requests are fine but a slice falls off a cliff — the tail blows up while the median holds.
Example alert
Exact wording varies — the detector generates titles from the anomaly it finds. This is representative of what an alert looks like when it fires.
How it works
Reads request spans and watches the tail spread (p99 relative to p50) per service. Fires when the recent spread is several times the baseline spread AND the median stayed flat — isolating tail-only degradation (a slow shard, GC pause, saturated pool) that a p95 check can miss. Severity floored by absolute tail latency.
Availability
Runs on these tiers:
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Open alerts in the sandbox →Related detectors
- Trace Latency Break
Catches a service whose request latency regressed against its own past — the whole distribution shifted slower.
- Trace Error Origin
Walks the span graph to find the origin service of an error cascade — where the failure started, not the services that merely reported it.
- Trace Throughput Drop
Catches a service whose request volume collapsed — crashed, deadlocked, or off the load balancer — when no slow or error spans give it away.
- Trace New Operation
Flags a service serving an operation it never served before — an unannounced deploy, a new endpoint, or a client calling a new path.