Use ConcurrentHashtable for telemetry log deduplication

[bric3]

What Does This Do

Replaces LogCollector's ConcurrentHashMap dedup storage with a bounded ConcurrentHashtable entry that carries its own atomic count. Duplicate lookups no longer construct RawLogMessage.

Migrates the direct tests to JUnit 5 and strengthens concurrency, capacity, and drain coverage.

Motivation

Telemetry logging can be reached repeatedly from error paths. The previous duplicate-hit path allocated a RawLogMessage on every call and retained a separate AtomicInteger per distinct message.

Additional Notes

Stacked on #11675.

The eight-thread duplicate-hit benchmark reduced normalized allocation from 48.000 B/op to approximately 0 B/op (about 1e-4 B/op measured).

Contributor Checklist

• Format the title according to the contribution guidelines
• Assign the type: and comp: or inst: labels in addition to any other useful labels
• Avoid using close, fix, or linking keywords when referencing an issue; use solves instead
• Update CODEOWNERS 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

[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	13.96 s	13.93 s	[-0.5%; +1.0%] (no difference)
startup:insecure-bank:tracing:Agent	12.91 s	13.01 s	[-1.4%; -0.1%] (maybe better)
startup:petclinic:appsec:Agent	17.01 s	16.86 s	[-0.1%; +1.9%] (no difference)
startup:petclinic:iast:Agent	16.96 s	17.04 s	[-1.2%; +0.3%] (no difference)
startup:petclinic:profiling:Agent	16.83 s	16.83 s	[-1.1%; +1.0%] (no difference)
startup:petclinic:sca:Agent	17.00 s	16.54 s	[+1.7%; +3.9%] (significantly worse)
startup:petclinic:tracing:Agent	16.17 s	16.16 s	[-0.9%; +1.0%] (no difference)

Commit: c1af8194 · 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.

[bric3]

@codex review

[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 2026-09-01T21:19:42.623545Z	1367128	Manual request

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[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Bravo.

Reviewed commit: 13671282ed

ℹ️ About Codex in GitHub

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