Separation of tags between metrics logs and traces fix

[Lewis-E]

What does this PR do?

• _dd.compute_stats is a marker for agent-side trace stats computation. We should isolate _dd.compute_stats to the serverless-init traces agent.
• Deal with the fact that we have DD_SERVERLESS_INIT_ENABLE_BACKEND_TRACE_STATS and DD_SERVERLESS_INIT_DISABLE_TRACE_STATS
• Remove unused BuildTracerTags function for clarity
• De-duplicated use of configured tags
• Renames all tag modification code to be a generalized place for agent tag changes, moved relevant functions into setup function.
• Update comments and tests

Motivation

• _dd.compute_stats should not show on logs or as a tag available for runtime metrics.
• If DD_SERVERLESS_INIT_ENABLE_BACKEND_TRACE_STATS is true, _dd.compute_stats should show on traces.
• If DD_SERVERLESS_INIT_ENABLE_BACKEND_TRACE_STATS is true andDD_SERVERLESS_INIT_DISABLE_TRACE_STATS is false, we should have accurate metric/trace data.
• If DD_SERVERLESS_INIT_ENABLE_BACKEND_TRACE_STATS is true andDD_SERVERLESS_INIT_DISABLE_TRACE_STATS is false, AND sampling is <1.0, we should have inaccurate metric trace data.

• Consistent pattern of tag modification

Describe how you validated your changes

• [x] Updated existing unit test

• [x] Test In-Container for cloudrun

• [x] Test In-Container for cloudrunjobs

• [x] Test In-Container for appservice

• [x] Test In-Container for containerapp

• Using the lewis/SVLS-4573/serverless-init-test-compute-stats self-monitoring branch

• [x] Test Sidecar for cloudrun in self-monitoring

• [x] Test Sidecar for appservice in self-monitoring

• [x] Test Sidecar for containerapp in self-monitoring

• Testing changes to the Azure App Services Extension

• [x] New unit test

• [ ] Test in AAS

[agent-platform-auto-pr[bot]]

Static quality checks

✅ Please find below the results from static quality gates Comparison made with ancestor 2441ad422ccb33dadd042c663452f1b07c2af1ed

Successful checks

Info

	Quality gate	Delta	On disk size (MiB)	Delta	On wire size (MiB)
✅	agent_deb_amd64	$${0}$$	$${705.41}$$ < $${707.13}$$	$${+0.01}$$	$${172.99}$$ < $${174.16}$$
✅	agent_deb_amd64_fips	$${0}$$	$${701.64}$$ < $${702.86}$$	$${-0.05}$$	$${172.21}$$ < $${173.5}$$
✅	agent_heroku_amd64	$${0}$$	$${327.72}$$ < $${327.92}$$	$${-0}$$	$${87.16}$$ < $${88.21}$$
✅	agent_msi	$${0}$$	$${571.12}$$ < $${982.08}$$	$${-0.03}$$	$${142.65}$$ < $${143.49}$$
✅	agent_rpm_amd64	$${0}$$	$${705.4}$$ < $${707.12}$$	$${-0}$$	$${176.11}$$ < $${177.29}$$
✅	agent_rpm_amd64_fips	$${0}$$	$${701.62}$$ < $${702.85}$$	$${+0.03}$$	$${175.1}$$ < $${176.32}$$
✅	agent_rpm_arm64	$${0}$$	$${687.27}$$ < $${691.67}$$	$${+0.04}$$	$${159.1}$$ < $${160.7}$$
✅	agent_rpm_arm64_fips	$${0}$$	$${684.33}$$ < $${687.54}$$	$${-0.01}$$	$${158.77}$$ < $${160.11}$$
✅	agent_suse_amd64	$${0}$$	$${705.4}$$ < $${707.12}$$	$${-0}$$	$${176.11}$$ < $${177.29}$$
✅	agent_suse_amd64_fips	$${0}$$	$${701.62}$$ < $${702.85}$$	$${+0.03}$$	$${175.1}$$ < $${176.32}$$
✅	agent_suse_arm64	$${0}$$	$${687.27}$$ < $${691.67}$$	$${+0.04}$$	$${159.1}$$ < $${160.7}$$
✅	agent_suse_arm64_fips	$${0}$$	$${684.33}$$ < $${687.54}$$	$${-0.01}$$	$${158.77}$$ < $${160.11}$$
✅	docker_agent_amd64	$${-0}$$	$${767.2}$$ < $${769.38}$$	$${-0}$$	$${260.51}$$ < $${262.06}$$
✅	docker_agent_arm64	$${-0}$$	$${773.64}$$ < $${778.35}$$	$${+0.01}$$	$${249.62}$$ < $${251.72}$$
✅	docker_agent_jmx_amd64	$${+0}$$	$${958.08}$$ < $${960.26}$$	$${-0.01}$$	$${329.14}$$ < $${330.69}$$
✅	docker_agent_jmx_arm64	$${-0}$$	$${953.24}$$ < $${957.95}$$	$${+0}$$	$${314.24}$$ < $${316.35}$$
✅	docker_cluster_agent_amd64	$${-0}$$	$${180.33}$$ < $${181.08}$$	$${-0}$$	$${63.71}$$ < $${64.49}$$
✅	docker_cluster_agent_arm64	$${+0}$$	$${196.19}$$ < $${198.49}$$	$${+0}$$	$${60.0}$$ < $${61.17}$$
✅	docker_cws_instrumentation_amd64	$${-0}$$	$${7.13}$$ < $${7.18}$$	$${-0}$$	$${2.99}$$ < $${3.33}$$
✅	docker_cws_instrumentation_arm64	$${0}$$	$${6.69}$$ < $${6.92}$$	$${+0}$$	$${2.73}$$ < $${3.09}$$
✅	docker_dogstatsd_amd64	$${0}$$	$${38.76}$$ < $${39.38}$$	$${-0}$$	$${15.0}$$ < $${15.82}$$
✅	docker_dogstatsd_arm64	$${0}$$	$${37.06}$$ < $${37.94}$$	$${-0}$$	$${14.33}$$ < $${14.83}$$
✅	dogstatsd_deb_amd64	$${0}$$	$${29.98}$$ < $${30.61}$$	$${-0}$$	$${7.93}$$ < $${8.79}$$
✅	dogstatsd_deb_arm64	$${0}$$	$${28.14}$$ < $${29.11}$$	$${-0}$$	$${6.81}$$ < $${7.71}$$
✅	dogstatsd_rpm_amd64	$${0}$$	$${29.98}$$ < $${30.61}$$	$${-0}$$	$${7.94}$$ < $${8.8}$$
✅	dogstatsd_suse_amd64	$${0}$$	$${29.98}$$ < $${30.61}$$	$${-0}$$	$${7.94}$$ < $${8.8}$$
✅	iot_agent_deb_amd64	$${0}$$	$${42.92}$$ < $${43.29}$$	$${+0}$$	$${11.23}$$ < $${12.04}$$
✅	iot_agent_deb_arm64	$${0}$$	$${40.05}$$ < $${40.92}$$	$${-0}$$	$${9.61}$$ < $${10.45}$$
✅	iot_agent_deb_armhf	$${0}$$	$${40.63}$$ < $${41.03}$$	$${-0}$$	$${9.8}$$ < $${10.62}$$
✅	iot_agent_rpm_amd64	$${0}$$	$${42.92}$$ < $${43.29}$$	$${-0}$$	$${11.25}$$ < $${12.06}$$
✅	iot_agent_suse_amd64	$${0}$$	$${42.92}$$ < $${43.29}$$	$${-0}$$	$${11.25}$$ < $${12.06}$$

[cit-pr-commenter[bot]]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: 337d643c-2f3e-4e92-b0a5-b5c95da9ebfd

Baseline: bb99c82e2fa90eae1f0de48071e02d3416b6f230 Comparison: 080a59dd6da254eb0366ea26399f1adc90cd2ef7 Diff

Optimization Goals: ✅ No significant changes detected

Experiments ignored for regressions

Regressions in experiments with settings containing erratic: true are ignored.

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	docker_containers_cpu	% cpu utilization	+0.47	[-2.57, +3.52]	1	Logs

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	quality_gate_metrics_logs	memory utilization	+1.63	[+1.41, +1.86]	1	Logs bounds checks dashboard
➖	ddot_logs	memory utilization	+0.81	[+0.73, +0.88]	1	Logs
➖	quality_gate_idle_all_features	memory utilization	+0.53	[+0.50, +0.57]	1	Logs bounds checks dashboard
➖	docker_containers_cpu	% cpu utilization	+0.47	[-2.57, +3.52]	1	Logs
➖	uds_dogstatsd_20mb_12k_contexts_20_senders	memory utilization	+0.33	[+0.27, +0.38]	1	Logs
➖	ddot_metrics_sum_cumulativetodelta_exporter	memory utilization	+0.06	[-0.17, +0.29]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	+0.04	[-0.39, +0.46]	1	Logs
➖	uds_dogstatsd_to_api_v3	ingress throughput	+0.01	[-0.11, +0.13]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	+0.00	[-0.41, +0.41]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	-0.00	[-0.08, +0.07]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	-0.00	[-0.13, +0.12]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	-0.02	[-0.07, +0.03]	1	Logs
➖	file_to_blackhole_500ms_latency	egress throughput	-0.05	[-0.43, +0.32]	1	Logs
➖	ddot_metrics_sum_delta	memory utilization	-0.06	[-0.26, +0.15]	1	Logs
➖	quality_gate_idle	memory utilization	-0.10	[-0.14, -0.05]	1	Logs bounds checks dashboard
➖	ddot_metrics	memory utilization	-0.12	[-0.35, +0.11]	1	Logs
➖	file_tree	memory utilization	-0.24	[-0.31, -0.17]	1	Logs
➖	otlp_ingest_logs	memory utilization	-0.27	[-0.37, -0.17]	1	Logs
➖	otlp_ingest_metrics	memory utilization	-0.32	[-0.47, -0.16]	1	Logs
➖	docker_containers_memory	memory utilization	-0.42	[-0.50, -0.35]	1	Logs
➖	quality_gate_logs	% cpu utilization	-0.46	[-1.94, +1.02]	1	Logs bounds checks dashboard
➖	tcp_syslog_to_blackhole	ingress throughput	-0.69	[-0.77, -0.61]	1	Logs
➖	ddot_metrics_sum_cumulative	memory utilization	-0.85	[-1.01, -0.69]	1	Logs

Bounds Checks: ✅ Passed

perf	experiment	bounds_check_name	replicates_passed	links
✅	docker_containers_cpu	simple_check_run	10/10
✅	docker_containers_memory	memory_usage	10/10
✅	docker_containers_memory	simple_check_run	10/10
✅	file_to_blackhole_0ms_latency	lost_bytes	10/10
✅	file_to_blackhole_0ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency	lost_bytes	10/10
✅	file_to_blackhole_1000ms_latency	memory_usage	10/10
✅	file_to_blackhole_100ms_latency	lost_bytes	10/10
✅	file_to_blackhole_100ms_latency	memory_usage	10/10
✅	file_to_blackhole_500ms_latency	lost_bytes	10/10
✅	file_to_blackhole_500ms_latency	memory_usage	10/10
✅	quality_gate_idle	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_idle	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_idle_all_features	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_idle_all_features	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_logs	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_logs	lost_bytes	10/10	bounds checks dashboard
✅	quality_gate_logs	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	cpu_usage	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	lost_bytes	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	memory_usage	10/10	bounds checks dashboard

Explanation

Confidence level: 90.00% Effect size tolerance: |Δ mean %| ≥ 5.00%

Performance changes are noted in the perf column of each table:

• ✅ = significantly better comparison variant performance
• ❌ = significantly worse comparison variant performance
• ➖ = no significant change in performance

A regression test is an A/B test of target performance in a repeatable rig, where "performance" is measured as "comparison variant minus baseline variant" for an optimization goal (e.g., ingress throughput). Due to intrinsic variability in measuring that goal, we can only estimate its mean value for each experiment; we report uncertainty in that value as a 90.00% confidence interval denoted "Δ mean % CI".

For each experiment, we decide whether a change in performance is a "regression" -- a change worth investigating further -- if all of the following criteria are true:

1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

2. Its 90.00% confidence interval "Δ mean % CI" does not contain zero, indicating that if our statistical model is accurate, there is at least a 90.00% chance there is a difference in performance between baseline and comparison variants.

3. Its configuration does not mark it "erratic".

CI Pass/Fail Decision

✅ Passed. All Quality Gates passed.

• quality_gate_idle, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_idle, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check lost_bytes: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_idle_all_features, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_idle_all_features, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check lost_bytes: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check cpu_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check intake_connections: 10/10 replicas passed. Gate passed.

[iadjivon]

Hi there, thanks for this PR. I've added a wip tag since it seems this is still being drafted. Please let us know once this is ready for review and we'll be happy to review! Thanks so much and let us know if you have any questions.

[Lewis-E]

how are we testing this? should we have some kind of self-monitoring alert for the resulting tagged things?

@apiarian-datadog There's a checklist for manual tests in the PR description under Describe how you validated your changes. Unchecked them all when going back into draft, and will re-test with the new code. Are there existing practices around monitors + combinations of env vars in self monitoring, given env vars can change per-deploy? I see there's some compute stats related code in the e2e tests. I have that repo on my to-onboard list, so adding tests there seems like a good next step to me.

[apiarian-datadog]

how are we testing this? should we have some kind of self-monitoring alert for the resulting tagged things?

@apiarian-datadog There's a checklist for manual tests in the PR description under Describe how you validated your changes. Unchecked them all when going back into draft, and will re-test with the new code. Are there existing practices around monitors + combinations of env vars in self monitoring, given env vars can change per-deploy? I see there's some compute stats related code in the e2e tests. I have that repo on my to-onboard list, so adding tests there seems like a good next step to me.

i think the existing trace stats tests should cover your trace stats needs on this one.

i suppose it might be worth adding a small test that creates an app with some tags and confirms that those tags (and the additional automatic ones) end up on the metrics, traces, and logs that we ingest. or perhaps this is an element of self-monitoring.

[Lewis-E]

/merge

[dd-devflow-routing-codex[bot]]

View all feedbacks in Devflow UI.

2025-12-11 18:32:22 UTC :information_source: Start processing command /merge

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devflow unqueued this merge request: It did not become mergeable within the expected time

[agent-platform-auto-pr[bot]]

Go Package Import Differences

Baseline: 2441ad422ccb33dadd042c663452f1b07c2af1ed Comparison: 080a59dd6da254eb0366ea26399f1adc90cd2ef7

binary	os	arch	change
trace-agent	linux	amd64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
trace-agent	linux	arm64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
trace-agent	windows	amd64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
trace-agent	darwin	amd64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
trace-agent	darwin	arm64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
heroku-trace-agent	linux	amd64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
otel-agent	linux	amd64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
otel-agent	linux	arm64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
full-host-profiler	linux	amd64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags
full-host-profiler	linux	arm64	+0, -1 -github.com/DataDog/datadog-agent/pkg/serverless/tags

[Lewis-E]

/merge

[dd-devflow-routing-codex[bot]]

View all feedbacks in Devflow UI.

2025-12-18 16:19:31 UTC :information_source: Start processing command /merge

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2025-12-18 16:19:37 UTC :information_source: MergeQueue: pull request added to the queue

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

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2025-12-18 17:16:35 UTC :information_source: MergeQueue: This merge request was merged