fix(metrics): match V3 resource mapping with Agent

[rayz]

Summary

Match the Datadog Agent’s V3 resource mapping behavior for series and sketches.

For V3 series, this promotes resource-style tags into V3 resources:

• device:<value> becomes a device resource and is removed from tags.
• Valid dd.internal.resource:<type>:<name> tags become resources and are removed from tags.
• Malformed dd.internal.resource:* tags are dropped.
• Resource order matches the Agent: host, device, then promoted resources.

For V3 sketches, this keeps device:* and dd.internal.resource:* as normal tags and only emits host as a resource, matching the Agent sketch path.

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

How did you test this PR?

References

[pr-commenter]

Regression Detector (Agent Data Plane)

Run ID: 47ad2953-685d-4842-9f60-22460b5ecb09
Baseline: 1ad7cde2 · Comparison: 2c514b83 · diff

Optimization Goals: ✅ No significant changes detected

Fine details of change detection per experiment (35)

Experiments configured erratic: true are tagged (ignored) and skipped when determining which experiments regressed or improved. Experiments which are detected as erratic at runtime are tagged (erratic) to flag that the run's sample dispersion was high, but their regression / improvement signal still counts.

experiment	goal	Δ mean %	links
dsd_uds_512kb_3k_contexts_cpu (erratic)	cpu	⚪ +6.05	metrics profiles logs
quality_gates_rss_idle	memory	⚪ +2.06	metrics profiles logs
dsd_uds_10mb_3k_contexts_memory	memory	⚪ +1.20	metrics profiles logs
quality_gates_rss_dsd_low	memory	⚪ +1.04	metrics profiles logs
otlp_ingest_metrics_5mb_cpu (erratic)	cpu	⚪ +0.90	metrics profiles logs
dsd_uds_1mb_3k_contexts_memory	memory	⚪ +0.88	metrics profiles logs
otlp_ingest_traces_5mb_throughput	throughput	⚪ -0.83	metrics profiles logs
quality_gates_rss_dsd_medium	memory	⚪ +0.82	metrics profiles logs
dsd_uds_512kb_3k_contexts_memory	memory	⚪ +0.72	metrics profiles logs
dsd_uds_100mb_3k_contexts_memory	memory	⚪ +0.65	metrics profiles logs
otlp_ingest_logs_5mb_cpu (ignored)	cpu	⚪ +0.63	metrics profiles logs
dsd_uds_100mb_3k_contexts_cpu (erratic)	cpu	⚪ +0.60	metrics profiles logs
dsd_uds_500mb_3k_contexts_memory	memory	⚪ +0.59	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_cpu (erratic)	cpu	⚪ +0.47	metrics profiles logs
otlp_ingest_traces_5mb_cpu (erratic)	cpu	⚪ +0.43	metrics profiles logs
dsd_uds_500mb_3k_contexts_cpu (erratic)	cpu	⚪ +0.36	metrics profiles logs
otlp_ingest_metrics_5mb_memory	memory	⚪ +0.35	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_memory	memory	⚪ +0.30	metrics profiles logs
quality_gates_rss_dsd_ultraheavy	memory	⚪ +0.16	metrics profiles logs
otlp_ingest_traces_5mb_memory	memory	⚪ +0.14	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_memory	memory	⚪ +0.11	metrics profiles logs
dsd_uds_10mb_3k_contexts_throughput	throughput	⚪ -0.01	metrics profiles logs
dsd_uds_1mb_3k_contexts_throughput	throughput	⚪ -0.00	metrics profiles logs
dsd_uds_512kb_3k_contexts_throughput	throughput	⚪ -0.00	metrics profiles logs
dsd_uds_100mb_3k_contexts_throughput	throughput	⚪ +0.00	metrics profiles logs
quality_gates_rss_dsd_heavy	memory	⚪ -0.01	metrics profiles logs
otlp_ingest_metrics_5mb_throughput	throughput	⚪ +0.02	metrics profiles logs
otlp_ingest_logs_5mb_throughput (ignored)	throughput	⚪ +0.03	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_throughput	throughput	⚪ +0.03	metrics profiles logs
dsd_uds_500mb_3k_contexts_throughput	throughput	⚪ +0.08	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_throughput	throughput	⚪ +0.09	metrics profiles logs
dsd_uds_10mb_3k_contexts_cpu (erratic)	cpu	⚪ -0.68	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_cpu (erratic)	cpu	⚪ -1.06	metrics profiles logs
otlp_ingest_logs_5mb_memory (ignored)	memory	⚪ -6.23	metrics profiles logs
dsd_uds_1mb_3k_contexts_cpu (erratic)	cpu	🟢 -10.78	metrics profiles logs

Bounds Checks: ✅ Passed (5)

experiment	check	replicates	observed	links
quality_gates_rss_dsd_heavy	memory_usage	10/10	✅ 122 MiB ≤ 140 MiB	metrics profiles logs
quality_gates_rss_dsd_low	memory_usage	10/10	✅ 40.2 MiB ≤ 50 MiB	metrics profiles logs
quality_gates_rss_dsd_medium	memory_usage	10/10	✅ 60.5 MiB ≤ 75 MiB	metrics profiles logs
quality_gates_rss_dsd_ultraheavy	memory_usage	10/10	✅ 177 MiB ≤ 200 MiB	metrics profiles logs
quality_gates_rss_idle	memory_usage	10/10	✅ 27.2 MiB ≤ 40 MiB	metrics profiles logs

Explanation

A change is flagged as a regression when |Δ mean %| > 5.00% in the regressing direction for its optimization goal AND SMP marks the experiment as a regression (is_regression: true). Improvements use the matching criteria for the improving direction. Experiments configured erratic: true (tagged (ignored)) are skipped outright; experiments detected as erratic at runtime (tagged (erratic)) still count, since that flag describes sample dispersion rather than directional certainty. The Δ mean % cell is colored accordingly: 🟢 = improvement, 🔴 = regression, ⚪ = neutral. Reduction in CPU or memory is an improvement; reduction in ingress throughput is a regression.

[Copilot]

Pull request overview

Aligns Saluki’s Datadog V3 metrics encoding with the Datadog Agent’s resource mapping semantics, especially around promoting device:* and dd.internal.resource:* tags into V3 “resources” for series while keeping sketch behavior unchanged.

Changes:

• Updated V3 series encoding to promote device:* and well-formed dd.internal.resource:<type>:<name> tags into resources (and remove them from tags), with resource ordering matching the Agent.
• Updated V3 sketch encoding to not promote device:* / dd.internal.resource:* tags (keeps them as tags) and only emit host as a resource.
• Added unit tests asserting tag/resource behavior and ordering for series vs sketches.

---

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[tobz]

Copilot sounds on point here, but I think all that matters is how Agent is doing it, which I'll leave to you to double check and fix here if necessary.

[rayz]

Seems weird but it is what the Agent does. Agent only treats tags as internal resource tags if they start with dd.internal.resource: so dd.internal.resource would be kept

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Drop malformed internal resource tags from series

When a V3 series includes a malformed reserved tag with no value, such as the bare tag dd.internal.resource, this predicate returns false and the filter above keeps it as a normal metric tag. The previous starts_with("dd.internal.resource") filter dropped these reserved-prefix tags, and the commit message says malformed dd.internal.resource:* tags should be dropped; leaking them into the V3 tagset makes ADP diverge from the Agent behavior for malformed resource markers.

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[pr-commenter]

Binary Size Analysis (Agent Data Plane)

Baseline: 1ad7cde · Comparison: 2c514b8 · diff
Analysis Configuration: stripped binaries · Pass/Fail Threshold: +5%
Sizes: 37.65 MiB (baseline) vs 37.97 MiB (comparison)
Size Change: +327.95 KiB (+0.85%)

✅ Binary size difference within threshold

Changes by Module

Module	File Size	Symbols
saluki_components::encoders::datadog	+83.20 KiB	356
core	+53.09 KiB	14500
anyhow	+39.34 KiB	1699
alloc	+37.12 KiB	2408
hyper	+27.84 KiB	584
saluki_components::sources::otlp	-21.76 KiB	236
hashbrown	+21.32 KiB	1115
figment	+20.92 KiB	700
[sections]	+17.78 KiB	9
piecemeal	-14.05 KiB	31
axum	+13.12 KiB	428
chrono	-13.08 KiB	23
tokio	+11.44 KiB	4515
http	+11.34 KiB	418
serde_core	+10.89 KiB	889
hyper_util	-10.21 KiB	139
http_body_util	-9.12 KiB	208
h2	+9.03 KiB	779
saluki_components::common::datadog	+8.70 KiB	440
tracing	-8.11 KiB	175

Detailed Symbol Changes

    FILE SIZE        VM SIZE    
 --------------  -------------- 
  +1.6%  +327Ki  +1.6%  +259Ki    [47045 Others]
  [NEW]  +136Ki  [NEW]  +136Ki    agent_data_plane::cli::run::handle_run_command::_{{closure}}::hf265beba717a8ffb
  [NEW] +66.7Ki  [NEW] +66.5Ki    saluki_core::topology::built::BuiltTopology::spawn::_{{closure}}::hef6f38503239c166
  [NEW] +66.1Ki  [NEW] +66.0Ki    agent_data_plane::cli::run::create_topology::_{{closure}}::hdcdf70adbde87ffc
  [NEW] +58.7Ki  [NEW] +58.5Ki    agent_data_plane::internal::env::workload::build_collector::_{{closure}}::ha56b75595a60c965
  [NEW] +58.2Ki  [NEW] +58.0Ki    saluki_core::topology::blueprint::TopologyBlueprint::build::_{{closure}}::hacbbeaf29f1d76dc
  [NEW] +57.1Ki  [NEW] +56.9Ki    agent_data_plane::internal::env::ADPEnvironmentProvider::from_configuration::_{{closure}}::hb77df6cc347f39b1
  [NEW] +56.7Ki  [NEW] +56.5Ki    agent_data_plane::cli::debug::handle_debug_command::_{{closure}}::ha2e6796c57380dae
  [NEW] +56.0Ki  [NEW] +55.8Ki    agent_data_plane::cli::dogstatsd::handle_dogstatsd_command::_{{closure}}::hb45f834f247c7f00
  [NEW] +49.8Ki  [NEW] +49.5Ki    agent_data_plane::main::_{{closure}}::hafe55c655b44bc0f
  [NEW] +49.7Ki  [NEW] +49.6Ki    core::ops::function::FnOnce::call_once::he29f19ec791745c2
  [DEL] -48.9Ki  [DEL] -48.8Ki    core::ops::function::FnOnce::call_once::h669ff363e842dff3
  [DEL] -49.7Ki  [DEL] -49.4Ki    agent_data_plane::main::_{{closure}}::h7d49a9469c34b899
  [DEL] -56.5Ki  [DEL] -56.3Ki    agent_data_plane::cli::dogstatsd::handle_dogstatsd_command::_{{closure}}::he79b0808df75cda1
  [DEL] -56.6Ki  [DEL] -56.4Ki    agent_data_plane::cli::debug::handle_debug_command::_{{closure}}::h7c655b6902e2f89a
  [DEL] -57.1Ki  [DEL] -56.9Ki    agent_data_plane::internal::env::ADPEnvironmentProvider::from_configuration::_{{closure}}::ha0920a2b79b02cce
  [DEL] -57.8Ki  [DEL] -57.6Ki    saluki_core::topology::blueprint::TopologyBlueprint::build::_{{closure}}::h32219546faa6f65a
  [DEL] -58.4Ki  [DEL] -58.2Ki    agent_data_plane::internal::env::workload::build_collector::_{{closure}}::ha8e6b4b93de14a84
  [DEL] -66.2Ki  [DEL] -66.0Ki    saluki_core::topology::built::BuiltTopology::spawn::_{{closure}}::hfe1e9d26bba4c0cd
  [DEL] -66.3Ki  [DEL] -66.1Ki    agent_data_plane::cli::run::create_topology::_{{closure}}::h9611a56813a60eb8
  [DEL]  -136Ki  [DEL]  -136Ki    agent_data_plane::cli::run::handle_run_command::_{{closure}}::h4399bd59161f275e
  +0.9%  +327Ki  +0.8%  +260Ki    TOTAL