🪞 12279 - Fix span link span ID hex padding by mcculls · Pull Request #12356 · DataDog/dd-trace-java

mcculls · 2026-09-01T07:32:05Z

This PR mirrors the changes from the original community contribution to enable CI testing with maintainer privileges.

Original PR: #12279
Original Author: @itsamenathan
Original Branch: itsamenathan/dd-trace-java:fix/pad-span-link-span-id-hex

Closes #12279

This is an automated mirror created to run CI checks. See tooling/mirror-community-pull-request.sh for details.

DDSpanLink serialises link ids into the _dd.span_links tag with DDTraceId.toHexString for the trace id, which pads to 32 characters, but DDSpanId.toHexString for the span id, which delegates to Long.toHexString and strips leading zeros. Span ids are generated as non-zero positive longs, so the leading hex nibble is zero for one id in eight and those ids serialise to 15 characters or fewer. Consumers that treat the field as fixed-width hex reject them: the OpenTelemetry Collector's Datadog receiver calls SpanIDFromHex, which requires exactly 16 characters, and drops the link. The trace id is unaffected because both DD64bTraceId and DD128bTraceId pad to 32. Use DDSpanId.toHexStringPadded, which is the existing padded variant on the same class, so the emitted id is always 16 characters.

dd-octo-sts · 2026-09-01T07:32:15Z

Hi! 👋 Thanks for your pull request! 🎉

To help us review it, please make sure to:

Add at least one type, and one component or instrumentation label to the pull request

If you need help, please check our contributing guidelines.

datadog-datadog-prod-us1

More details

The encoder now writes each span-link span ID as a 16-character hexadecimal string. It keeps all leading zeroes.

Was this helpful? React 👍 or 👎

_{Open Bits AI session}

_{🤖 Datadog Autotest · Commit 2ee853c · What is Autotest? · @DataDog review to ask questions · Any feedback? Reach out in #autotest}

…pan ids

dd-octo-sts · 2026-09-01T08:14:17Z

🟢 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	13.99 s	[-1.0%; +1.1%] (no difference)
startup:insecure-bank:tracing:Agent	12.92 s	13.02 s	[-1.4%; -0.0%] (maybe better)
startup:petclinic:appsec:Agent	17.42 s	17.31 s	[-0.2%; +1.4%] (no difference)
startup:petclinic:iast:Agent	17.35 s	17.49 s	[-1.6%; -0.0%] (maybe better)
startup:petclinic:profiling:Agent	17.38 s	17.30 s	[-0.6%; +1.6%] (no difference)
startup:petclinic:sca:Agent	17.46 s	16.49 s	[+1.5%; +10.3%] (significantly worse)
startup:petclinic:tracing:Agent	16.60 s	16.72 s	[-1.8%; +0.3%] (no difference)

Commit: 4f24ed86 · CI Pipeline · Benchmarking Platform UI

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 · 2026-09-01T14:20:44Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-09-01T14:20:49Z

View all feedbacks in Devflow UI.

2026-09-01 14:20:48 UTC ℹ️ Start processing command /merge

2026-09-01 14:20:53 UTC ℹ️ MergeQueue: pull request added to the queue

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

2026-09-01 14:49:02 UTC ❌ MergeQueue: The build pipeline contains failing jobs for this merge request

Build pipeline has failing jobs for 5118a35:

K8S_LIB_INJECTION: [dd-lib-java-init-test-app, ${PRIVATE_DOCKER_REGISTRY}/system-tests/dd-lib-java-init-test-app, 235494822917.dkr.ecr.us-east-1.amazonaws.com/ssi/cluster-agent:7.82.2, 235494822917.dkr.ecr.us-east-1.amazonaws.com/ssi/apm-inject:latest, 3.240.0, 235494822917.dkr.ecr.us-east-1.amazonaws.com/ssi/dd-lib-java-init:glci134624890]

⚠️ Do NOT retry failed jobs directly (why?).

What to do next?

Investigate the failures and when ready, re-add your pull request to the queue!
If your PR checks are green, try to rebase/merge. It might be because the CI run is a bit old.
Any question, go check the FAQ.

Details

Since those jobs are not marked as being allowed to fail, the pipeline will most likely fail.
Therefore, and to allow other builds to be processed, this merge request has been rejected and the pipeline got canceled.

dd-octo-sts · 2026-09-01T15:00:03Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-09-01T15:00:06Z

View all feedbacks in Devflow UI.

2026-09-01 15:00:06 UTC ℹ️ Start processing command /merge

2026-09-01 15:00:12 UTC ℹ️ MergeQueue: pull request added to the queue

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

2026-09-01 15:56:47 UTC ℹ️ MergeQueue: This merge request was merged

mcculls requested a review from a team as a code owner September 1, 2026 07:32

mcculls requested review from ValentinZakharov and removed request for a team September 1, 2026 07:32

datadog-datadog-prod-us1 Bot reviewed Sep 1, 2026

View reviewed changes

This comment has been minimized.

Sign in to view

Cleanup comment about expected _dd.span_links padding for trace and s…

2ab06dc

…pan ids

mcculls added type: bug fix Bug fix comp: core Tracer core tag: community Community contribution labels Sep 1, 2026

Merge remote-tracking branch 'origin/master' into community-pr-12279

4f24ed8

mcculls requested a review from AlexeyKuznetsov-DD September 1, 2026 13:39

AlexeyKuznetsov-DD approved these changes Sep 1, 2026

View reviewed changes

mcculls enabled auto-merge September 1, 2026 13:41

mcculls added this pull request to the merge queue Sep 1, 2026

github-merge-queue Bot removed this pull request from the merge queue due to failed status checks Sep 1, 2026

mcculls added this pull request to the merge queue Sep 1, 2026

github-merge-queue Bot removed this pull request from the merge queue due to failed status checks Sep 1, 2026

gh-worker-dd-mergequeue-cf854d Bot merged commit fb408c3 into master Sep 1, 2026
602 checks passed

gh-worker-dd-mergequeue-cf854d Bot deleted the community-pr-12279 branch September 1, 2026 15:56

github-actions Bot added this to the 1.66.0 milestone Sep 1, 2026

Navigation Menu

Uh oh!

🪞 12279 - Fix span link span ID hex padding - #12356

🪞 12279 - Fix span link span ID hex padding#12356
gh-worker-dd-mergequeue-cf854d[bot] merged 3 commits into
masterfrom
community-pr-12279

mcculls commented Sep 1, 2026

Uh oh!

dd-octo-sts Bot commented Sep 1, 2026

Uh oh!

datadog-datadog-prod-us1 Bot left a comment

Uh oh!

This comment has been minimized.

dd-octo-sts Bot commented Sep 1, 2026 •

edited

Loading

Uh oh!

dd-octo-sts Bot commented Sep 1, 2026

Uh oh!

gh-worker-devflow-routing-ef8351 Bot commented Sep 1, 2026 •

edited

Loading

Uh oh!

Uh oh!

dd-octo-sts Bot commented Sep 1, 2026

Uh oh!

gh-worker-devflow-routing-ef8351 Bot commented Sep 1, 2026 •

edited

Loading

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Uh oh!

Conversation

mcculls commented Sep 1, 2026

Uh oh!

dd-octo-sts Bot commented Sep 1, 2026

Uh oh!

datadog-datadog-prod-us1 Bot left a comment

Choose a reason for hiding this comment

Uh oh!

This comment has been minimized.

dd-octo-sts Bot commented Sep 1, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

🟢 Java Benchmark SLOs — All performance SLOs passed

Uh oh!

dd-octo-sts Bot commented Sep 1, 2026

Uh oh!

gh-worker-devflow-routing-ef8351 Bot commented Sep 1, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

What to do next?

Uh oh!

Uh oh!

dd-octo-sts Bot commented Sep 1, 2026

Uh oh!

gh-worker-devflow-routing-ef8351 Bot commented Sep 1, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

dd-octo-sts Bot commented Sep 1, 2026 •

edited

Loading

gh-worker-devflow-routing-ef8351 Bot commented Sep 1, 2026 •

edited

Loading

gh-worker-devflow-routing-ef8351 Bot commented Sep 1, 2026 •

edited

Loading