Prevent Akka HTTP timeout cleanup from retaining request context

[amarziali]

What Does This Do

Disable async context capture only while TimeoutAccessImpl.clear() registers its timeout-cancellation callback, using the existing async-propagation-disable instrumentation.

Add an exact class-filter exception for TimeoutAccessImpl. The existing TimeoutAccessImpl$* entry covers nested classes, not the enclosing class containing clear().

Motivation

Play 2.6–2.8 smoke diagnostics exposed unresolved continuations captured by this cleanup callback. It waits on request-entity completion, which can remain unresolved even after the response completes.

This callback only cancels a timer; it does not need request context. Actual timeout handlers and normal request propagation remain unchanged.

flowchart LR
    A[Response completes] --> B[TimeoutAccessImpl.clear]
    B --> C[Register cancellation callback]
    C --> D[Wait for entity completion]
    D --> E[Cancel timeout task]
    B -. Previously captured request context .-> F[Unresolved continuation]
    style F fill:#f8d7da,stroke:#dc3545
    style C fill:#d4edda,stroke:#28a745

Loading

Here we remove the unwanted context capture without changing cancellation behavior.

Additional Notes

Contributor Checklist

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  Use solves instead, and assign the PR milestone to the issue
• Update the CODEOWNERS file on source file addition, migration, or deletion
• Update public documentation with any new configuration flags or behaviors
• Once approved, use merge queue to merge the PR

Jira ticket: [PROJ-IDENT]

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-23T15:39:44.791397Z	642f7bd	PR opened
🔒 Security Review	✅ Completed 2026-09-23T15:37:10.138881Z	642f7bd	PR opened

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[datadog-datadog-prod-us1-2]

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 59.28% (-0.03%)

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: 642f7bd | Docs | Give us feedback!}

[datadog-datadog-prod-us1-2]

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[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	14.00 s	13.89 s	[+0.0%; +1.5%] (maybe worse)
startup:insecure-bank:tracing:Agent	12.99 s	13.02 s	[-1.0%; +0.5%] (no difference)
startup:petclinic:appsec:Agent	17.63 s	16.81 s	[+0.6%; +9.2%] (maybe worse)
startup:petclinic:iast:Agent	16.84 s	17.56 s	[-8.2%; -0.0%] (maybe better)
startup:petclinic:profiling:Agent	17.24 s	17.32 s	[-1.5%; +0.6%] (no difference)
startup:petclinic:sca:Agent	17.60 s	17.51 s	[-0.5%; +1.6%] (no difference)
startup:petclinic:tracing:Agent	16.25 s	16.31 s	[-6.3%; +5.5%] (unstable)

Commit: 642f7bda · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[dd-octo-sts]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-09-25 13:36:58 UTC ℹ️ Start processing command /merge

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2026-09-25 13:37:03 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in master is approximately 1h (p90).

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2026-09-25 14:53:22 UTC ℹ️ MergeQueue: This merge request was merged