Fix assumptions about what a top_level span is

[bwoebi]

Otherwise span stats will be broken for nested services.

Also properly handling version propagation, its removal according to UST was too aggressive until now.

[chatgpt-codex-connector]

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[datadog-prod-us1-3]

 

✨ Fix all issues with BitsAI

⚠️ Warnings

🚦 7 Pipeline jobs failed

DataDog/apm-reliability/dd-trace-php | ASAN test_c with multiple observers: [8.3]     

DataDog/apm-reliability/dd-trace-php | ASAN test_c with multiple observers: [8.5]     

DataDog/apm-reliability/dd-trace-php | pecl tests: [7.0]     

View all 7 failed jobs.

ℹ️ Info

No other issues found (see more)

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 54.12% (+0.00%)

Useful? React with 👍 / 👎

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: c01e428 | Docs | Datadog PR Page | Give us feedback!}

[pr-commenter]

Benchmarks [ tracer ]

Benchmark execution time: 2026-06-05 17:17:48

Comparing candidate commit c01e428 in PR branch bob/fix-span-stats with baseline commit 87f1683 in branch master.

Found 1 performance improvements and 13 performance regressions! Performance is the same for 180 metrics, 0 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

• 🟩 = significantly better candidate vs. baseline
• 🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

scenario:MessagePackSerializationBench/benchMessagePackSerialization-opcache

• 🟩 execution_time [-4.065µs; -2.915µs] or [-3.672%; -2.632%]

scenario:PDOBench/benchPDOOverhead

• 🟥 execution_time [+21.406µs; +25.573µs] or [+8.735%; +10.435%]

scenario:PDOBench/benchPDOOverhead-opcache

• 🟥 execution_time [+13.592µs; +16.120µs] or [+5.569%; +6.604%]

scenario:PDOBench/benchPDOOverheadWithDBM

• 🟥 execution_time [+20.536µs; +22.821µs] or [+8.334%; +9.261%]

scenario:PDOBench/benchPDOOverheadWithDBM-opcache

• 🟥 execution_time [+12.712µs; +15.459µs] or [+5.201%; +6.326%]

scenario:PHPRedisBench/benchRedisOverhead

• 🟥 execution_time [+97.153µs; +111.274µs] or [+10.056%; +11.518%]

scenario:PHPRedisBench/benchRedisOverhead-opcache

• 🟥 execution_time [+61.094µs; +70.621µs] or [+6.133%; +7.089%]

scenario:SpanBench/benchDatadogAPI

• 🟥 execution_time [+4.476µs; +6.742µs] or [+6.808%; +10.254%]

scenario:SpanBench/benchDatadogAPI-opcache

• 🟥 execution_time [+4.176µs; +5.971µs] or [+6.368%; +9.106%]

scenario:SpanBench/benchOpenTelemetryInteroperability

• 🟥 execution_time [+7.798µs; +10.794µs] or [+4.171%; +5.773%]

scenario:TraceFlushBench/benchFlushTrace

• 🟥 execution_time [+61.074µs; +94.726µs] or [+5.075%; +7.872%]

scenario:TraceFlushBench/benchFlushTrace-opcache

• 🟥 execution_time [+1.161ms; +1.191ms] or [+96.192%; +98.670%]

scenario:TraceSerializationBench/benchSerializeTrace

• 🟥 execution_time [+72.321µs; +84.179µs] or [+17.213%; +20.035%]

scenario:TraceSerializationBench/benchSerializeTrace-opcache

• 🟥 execution_time [+87.126µs; +98.774µs] or [+24.745%; +28.053%]

[github-actions]

Snapshots difference summary

The following differences have been observed in committed snapshots. It is meant to help the reviewer.
The diff is simplistic, so please check some files anyway while we improve it.

If you need to update snapshots, please refer to CONTRIBUTING.md

2 occurrences of :

- "span.kind": "client"
+ "span.kind": "client"
+ "version": "1.0"