feat(logs): corrective suggestions for backpressure status

[UTXOnly]

What does this PR do?

Adds a brief, stage-specific corrective suggestion to the "Logs Agent Backpressure" section of agent status. When a logs pipeline component is saturated, the section names the logs_config settings most relevant to that stage:

Saturated stage	Suggestion
processor	drop noisy logs with logs_config.processing_rules (exclude_at_match), or raise logs_config.pipelines
strategy	lower logs_config.compression_level, or raise logs_config.pipelines
worker / destination_*	raise logs_config.batch_max_concurrent_send, verify endpoint reachability (logs_config.logs_dd_url)
fallback	raise logs_config.pipelines

The suggestion tracks the component that drives the overall state (the one named in Reason). It is shown in the text and HTML status output and included in JSON as backpressure.suggestion (omitted when HEALTHY).

Motivation

The backpressure section tells a user which pipeline stage is saturated but not what to do about it. Surfacing the relevant logs_config knob inline turns the diagnosis into an actionable next step without requiring the user to go look up which setting governs that stage.

Describe how you validated your changes

• Unit tests (dda inv test --targets=./pkg/logs/status) assert each saturated stage produces a suggestion naming the relevant setting, and that a HEALTHY state carries none.
• Confirmed coverage maps every component that can surface a utilization signal — processor, strategy, worker, and destination_* (verified MonitorTag() always prefixes destination_); sender is capacity-only and is not shown.
• dda inv agent.build builds cleanly with the template change.

Additional Notes

• worker and destination intentionally share one "sending" suggestion since both bottleneck on destination throughput and tune via the same settings.

[datadog-datadog-prod-us1]

🎯 Code Coverage (details)
• Patch Coverage: 90.00%
• Overall Coverage: 50.61% (-0.00%)

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: 39539d9 | Docs | Datadog PR Page | Give us feedback!}

[dd-octo-sts]

Files inventory check summary

File checks results against ancestor 28445870:

Results for datadog-agent_7.81.0~devel.git.644.39539d9.pipeline.117827554-1_amd64.deb:

No change detected

[dd-octo-sts]

Static quality checks

✅ Please find below the results from static quality gates
Comparison made with ancestor 2844587
📊 Static Quality Gates Dashboard
🔗 SQG Job

Successful checks

Info

	Quality gate	Change	Size (prev → curr → max)
✅	agent_deb_amd64	+139.22 KiB (0.02% increase, -2.08% of buffer)	751.652 → 751.788 → 758.200
✅	agent_deb_amd64_fips	+135.16 KiB (0.02% increase, -5.46% of buffer)	707.423 → 707.555 → 709.840
✅	agent_heroku_amd64	+64.0 KiB (0.02% increase, -1.27% of buffer)	310.320 → 310.383 → 315.230
✅	agent_rpm_amd64	+139.22 KiB (0.02% increase, -2.08% of buffer)	751.636 → 751.772 → 758.170
✅	agent_rpm_amd64_fips	+135.16 KiB (0.02% increase, -5.42% of buffer)	707.407 → 707.539 → 709.840
✅	agent_rpm_arm64	+115.44 KiB (0.02% increase, -4.30% of buffer)	727.039 → 727.152 → 729.660
✅	agent_rpm_arm64_fips	+119.47 KiB (0.02% increase, -5.07% of buffer)	686.558 → 686.674 → 688.860
✅	agent_suse_amd64	+139.22 KiB (0.02% increase, -2.08% of buffer)	751.636 → 751.772 → 758.170
✅	agent_suse_amd64_fips	+135.16 KiB (0.02% increase, -5.42% of buffer)	707.407 → 707.539 → 709.840
✅	agent_suse_arm64	+115.44 KiB (0.02% increase, -4.30% of buffer)	727.039 → 727.152 → 729.660
✅	agent_suse_arm64_fips	+119.47 KiB (0.02% increase, -5.07% of buffer)	686.558 → 686.674 → 688.860
✅	docker_agent_amd64	+139.22 KiB (0.02% increase, -5.02% of buffer)	811.080 → 811.216 → 813.790
✅	docker_agent_arm64	+115.44 KiB (0.01% increase, -3.20% of buffer)	811.512 → 811.625 → 815.030
✅	docker_agent_jmx_amd64	+139.22 KiB (0.01% increase, -5.38% of buffer)	1002.021 → 1002.157 → 1004.550
✅	docker_agent_jmx_arm64	+115.44 KiB (0.01% increase, -3.13% of buffer)	991.106 → 991.218 → 994.710
✅	docker_cluster_agent_amd64	+56.03 KiB (0.03% increase, -7.64% of buffer)	209.753 → 209.808 → 210.470
✅	docker_cluster_agent_arm64	+64.0 KiB (0.03% increase, -47.16% of buffer)	222.847 → 222.910 → 222.980
✅	docker_dogstatsd_amd64	+20.0 KiB (0.05% increase, -28.41% of buffer)	39.841 → 39.861 → 39.910
✅	dogstatsd_deb_amd64	+16.0 KiB (0.05% increase, -2.41% of buffer)	30.502 → 30.518 → 31.150
✅	dogstatsd_deb_arm64	+16.0 KiB (0.05% increase, -1.51% of buffer)	28.499 → 28.514 → 29.530
✅	dogstatsd_rpm_amd64	+16.0 KiB (0.05% increase, -2.41% of buffer)	30.502 → 30.518 → 31.150
✅	dogstatsd_suse_amd64	+16.0 KiB (0.05% increase, -2.41% of buffer)	30.502 → 30.518 → 31.150
✅	iot_agent_deb_amd64	+56.0 KiB (0.12% increase, -8.84% of buffer)	45.762 → 45.816 → 46.380
✅	iot_agent_deb_arm64	+56.0 KiB (0.13% increase, -4.38% of buffer)	42.472 → 42.527 → 43.720
✅	iot_agent_deb_armhf	+60.0 KiB (0.14% increase, -8.50% of buffer)	43.270 → 43.329 → 43.960
✅	iot_agent_rpm_amd64	+56.0 KiB (0.12% increase, -8.85% of buffer)	45.762 → 45.817 → 46.380
✅	iot_agent_suse_amd64	+56.0 KiB (0.12% increase, -8.83% of buffer)	45.761 → 45.816 → 46.380

5 successful checks with minimal change (< 2 KiB)

	Quality gate	Current Size
✅	docker_cws_instrumentation_amd64	7.447 MiB
✅	docker_cws_instrumentation_arm64	6.877 MiB
✅	docker_dogstatsd_arm64	37.946 MiB
✅	docker_host_profiler_amd64	304.525 MiB
✅	docker_host_profiler_arm64	315.638 MiB

[cit-pr-commenter-54b7da]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: 12e7792d-5bb8-4948-b26c-04f21051f535

Baseline: 2844587
Comparison: 39539d9
Diff

Optimization Goals: ✅ No significant changes detected

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	quality_gate_idle	memory utilization	+0.26	[+0.21, +0.32]	1	Logs bounds checks dashboard
➖	quality_gate_metrics_logs	memory utilization	+0.08	[-0.17, +0.33]	1	Logs bounds checks dashboard
➖	quality_gate_idle_all_features	memory utilization	-0.18	[-0.22, -0.15]	1	Logs bounds checks dashboard
➖	quality_gate_logs	% cpu utilization	-2.28	[-3.33, -1.24]	1	Logs bounds checks dashboard

Bounds Checks: ✅ Passed

perf	experiment	bounds_check_name	replicates_passed	observed_value	links
✅	quality_gate_idle	intake_connections	10/10	3 ≤ 4	bounds checks dashboard
✅	quality_gate_idle	memory_usage	10/10	144.56MiB ≤ 147MiB	bounds checks dashboard
✅	quality_gate_idle	total_bytes_received	10/10	729.09KiB ≤ 819.20KiB	bounds checks dashboard
✅	quality_gate_idle_all_features	intake_connections	10/10	3 ≤ 4	bounds checks dashboard
✅	quality_gate_idle_all_features	memory_usage	10/10	475.52MiB ≤ 495MiB	bounds checks dashboard
✅	quality_gate_idle_all_features	total_bytes_received	10/10	1.13MiB ≤ 1.25MiB	bounds checks dashboard
✅	quality_gate_logs	intake_connections	10/10	3 ≤ 6	bounds checks dashboard
✅	quality_gate_logs	memory_usage	10/10	177.08MiB ≤ 195MiB	bounds checks dashboard
✅	quality_gate_logs	missed_bytes	10/10	0B = 0B	bounds checks dashboard
✅	quality_gate_logs	total_bytes_received	10/10	264.42MiB ≤ 292MiB	bounds checks dashboard
✅	quality_gate_metrics_logs	cpu_usage	10/10	347.69 ≤ 2000	bounds checks dashboard
✅	quality_gate_metrics_logs	intake_connections	10/10	4 ≤ 6	bounds checks dashboard
✅	quality_gate_metrics_logs	memory_usage	10/10	400.43MiB ≤ 430MiB	bounds checks dashboard
✅	quality_gate_metrics_logs	missed_bytes	10/10	0B = 0B	bounds checks dashboard
✅	quality_gate_metrics_logs	total_bytes_received	10/10	0.94GiB ≤ 1.04GiB	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".

Replicate Execution Details

We run multiple replicates for each experiment/variant. However, we allow replicates to be automatically retried if there are any failures, up to 8 times, at which point the replicate is marked dead and we are unable to run analysis for the entire experiment. We call each of these attempts at running replicates a replicate execution. This section lists all replicate executions that failed due to the target crashing or being oom killed.

Note: In the below tables we bucket failures by experiment, variant, and failure type. For each of these buckets we list out the replicate indexes that failed with an annotation signifying how many times said replicate failed with the given failure mode. In the below example the baseline variant of the experiment named experiment_with_failures had two replicates that failed by oom kills. Replicate 0, which failed 8 executions, and replicate 1 which failed 6 executions, all with the same failure mode.

Experiment	Variant	Replicates	Failure	Logs	Debug Dashboard
experiment_with_failures	baseline	0 (x8) 1 (x6)	Oom killed		Debug Dashboard

The debug dashboard links will take you to a debugging dashboard specifically designed to investigate replicate execution failures.

❌ Retried Profiling Replicate Execution Failures (ddprof)

Note: Profiling replicas may still be executing. See the debug dashboard for up to date status.

Experiment	Variant	Replicates	Failure	Debug Dashboard
quality_gate_idle	baseline	10	Oom killed	Debug Dashboard
quality_gate_idle	comparison	10	Oom killed	Debug Dashboard
quality_gate_idle_all_features	baseline	10	Oom killed	Debug Dashboard
quality_gate_idle_all_features	comparison	10	Oom killed	Debug Dashboard
quality_gate_logs	baseline	10	Oom killed	Debug Dashboard
quality_gate_logs	comparison	10	Oom killed	Debug Dashboard
quality_gate_metrics_logs	baseline	10	Oom killed	Debug Dashboard
quality_gate_metrics_logs	comparison	10	Oom killed	Debug Dashboard

CI Pass/Fail Decision

✅ Passed. All Quality Gates passed.

• quality_gate_metrics_logs, bounds check total_bytes_received: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check missed_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_idle_all_features, bounds check memory_usage: 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 total_bytes_received: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check total_bytes_received: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check missed_bytes: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_logs, 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_idle, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_idle, bounds check total_bytes_received: 10/10 replicas passed. Gate passed.