Bench/trace id hex utilities

[xlamorlette-datadog]

This is a draft pull request to run all CI jobs for the following PR from a fork: #311.

[datadog-datadog-prod-us1-2]

✨ Fix all issues with BitsAI

⚠️ Warnings

🚦 13 Pipeline jobs failed

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Internal Error: API key is missing

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Development | build-linux-cmake (llvm, arm64)     

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ℹ️ Info

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 90.86% (+0.00%)

Useful? React with 👍 / 👎

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[pr-commenter]

Benchmarks

Benchmark execution time: 2026-05-26 09:41:50

Comparing candidate commit 3e8fece in PR branch bench/trace-id-hex-utilities with baseline commit 90d9267 in branch main.

Some scenarios are present only in baseline or only in candidate runs. If you didn't create or remove some scenarios in your branch, this maybe a sign of crashed benchmarks 💥💥💥
Check Gitlab CI job log to find if any benchmark has crashed.

Scenarios present only in candidate:

• BM_TraceID_ParseHex/128bit
• BM_TraceID_HexPadded/NoPadding
• BM_Hex_uint64
• BM_HexPadded_uint64/WorstCasePadding
• BM_HexPadded_uint64/NoPadding
• BM_TraceID_HexPadded/WithPadding
• BM_TraceID_ParseHex/64bit

Found 1 performance improvements and 0 performance regressions! Performance is the same for 0 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:BM_TraceTinyCCSource

• 🟩 execution_time [-3.748ms; -3.360ms] or [-4.741%; -4.251%]

[xlamorlette-datadog]

This was just to check #311.