> ## Documentation Index
> Fetch the complete documentation index at: https://docs.basset.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# queue.latency

> How long work waits before the main queue runs it

A probe block resubmitted to the main queue every window. One reading per
window regardless of activity, reporting the worst wait it saw.

| | |
| - | - |
| [Delivery](/instruments/metadata) | stream, interval |
| Mechanism | none |
| [Requires](/instruments/metadata) | iOS 17+, basset 0.1.1+ |

Real output from `basset request get`, captured against a running app:

```
CAPTURED                  ELAPSED  INSTRUMENT

launch 7444895511331759249
2026-08-23T14:26:34.443Z  +0.0s    concurrency.queue.latency(dispatchQueue)
├─ queueLabel               main
├─ queueLatencyNanoseconds  108292
├─ windowNanoseconds        999983250
└─ occurrenceCount          1
2026-08-23T14:26:35.442Z  +1.0s    concurrency.queue.latency(dispatchQueue)
├─ queueLabel               main
├─ queueLatencyNanoseconds  163291
├─ windowNanoseconds        999667000
└─ occurrenceCount          1
2026-08-23T14:26:36.442Z  +2.0s    concurrency.queue.latency(dispatchQueue)
├─ queueLabel               main
├─ queueLatencyNanoseconds  177458
├─ windowNanoseconds        999416625
└─ occurrenceCount          1
```


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