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Merged
merged 16 commits into from
Sep 10, 2025
Merged

[OTEL] Metrics API Support - Configurations & Telemetry #7420

merged 16 commits into from
Sep 10, 2025

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@link04
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@link04 link04 commented Aug 20, 2025 •
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Summary of changes

This PR implements configuration parsing needed for OpenTelemetry OTLP Metrics Collecting and Exporting as part of the broader OpenTelemetry Metrics API support RFC. Key additions include:

  • OTLP Configuration Keys: Added all standard OpenTelemetry environment variables for metrics export configuration
  • Fallback Hierarchy: Implemented proper fallback from metrics-specific configs to general OTLP configs to defaults

This is the first of a series of 3 PRs I hope to put together to complete this work.

  1. [OTEL] Metrics API Support - Configurations & Telemetry #7420 <- You are here.
  2. [OTEL] Metrics API Support - Collection Implementation #7511
  3. [OTEL] Metrics API Support - Metrics Reader & OTLP Exporter #7514

Reason for change

The [RFC] OpenTelemetry Metrics API support requires the .NET tracer to act as a drop-in replacement for the OpenTelemetry SDK, allowing customers to migrate from OTel SDK to Datadog SDK with zero friction. This requires supporting all standard OpenTelemetry configuration environment variables for metrics export.
Business Impact: Enables customers using OpenTelemetry Metrics API to switch to Datadog without code changes, supporting our strategic initiative to be OTel-native.

Implementation details

Added the configurations below, for some I needed to add both metrics configs and fallbacks also tracer settings, for others I needed to add only testing and to telemetry. ✅ Added | 🟣 Updated | 🟦 Untouched

Datadog SDK Configurations (2/2):
1. DD_METRICS_OTEL_ENABLED - 🟣
2. DD_TAGS - 🟦

OpenTelemetry Metrics SDK Configurations (4/4):
1. OTEL_RESOURCE_ATTRIBUTES - 🟦
2. OTEL_METRICS_EXPORTER - 🟣
3. OTEL_METRIC_EXPORT_INTERVAL - ✅
4. OTEL_METRIC_EXPORT_TIMEOUT - ✅

OTLP Exporter Configurations (9/9):
1. OTEL_EXPORTER_OTLP_METRICS_PROTOCOL - ✅
2. OTEL_EXPORTER_OTLP_METRICS_ENDPOINT - ✅
3. OTEL_EXPORTER_OTLP_METRICS_HEADERS - ✅
4. OTEL_EXPORTER_OTLP_METRICS_TIMEOUT - ✅
5. OTEL_EXPORTER_OTLP_PROTOCOL (fallback) - ✅
6. OTEL_EXPORTER_OTLP_ENDPOINT (fallback) - ✅
7. OTEL_EXPORTER_OTLP_HEADERS (fallback) - ✅
8. OTEL_EXPORTER_OTLP_TIMEOUT (fallback) - ✅
9. OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE - ✅

Test coverage

Added to TracerSettingsTests different tests for each configuration combos and fallbacks expected behavior, also accounting for customers adding invalid/unsupported inputs for the multiple choice configs.
(Will add/update the tests as the other PRs are coming to completion).

Other details

Jira: APMAPI-1571

link04 and others added 4 commits August 18, 2025 18:44
@link04 link04 requested a review from a team as a code owner August 20, 2025 00:29
@link04 link04 force-pushed the maximo/otel-metrics-api-configs branch from df4a8f7 to 1748358 Compare August 20, 2025 00:31
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dd-trace-dotnet-ci-bot bot commented Aug 20, 2025 •
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Execution-Time Benchmarks Report ⏱️

Execution-time results for samples comparing the following branches/commits:

Execution-time benchmarks measure the whole time it takes to execute a program. And are intended to measure the one-off costs. Cases where the execution time results for the PR are worse than latest master results are shown in red. The following thresholds were used for comparing the execution times:

  • Welch test with statistical test for significance of 5%
  • Only results indicating a difference greater than 5% and 5 ms are considered.

Note that these results are based on a single point-in-time result for each branch. For full results, see the dashboard.

Graphs show the p99 interval based on the mean and StdDev of the test run, as well as the mean value of the run (shown as a diamond below the graph).

gantt
    title Execution time (ms) FakeDbCommand (.NET Framework 4.8) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (71ms)  : 71, 72
     .   : milestone, 71,
    master - mean (72ms)  : 71, 73
     .   : milestone, 72,

    section Baseline
    This PR (7420) - mean (69ms)  : 64, 74
     .   : milestone, 69,
    master - mean (69ms)  : 63, 75
     .   : milestone, 69,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (992ms)  : 968, 1016
     .   : milestone, 992,
    master - mean (991ms)  : 961, 1020
     .   : milestone, 991,
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gantt
    title Execution time (ms) FakeDbCommand (.NET Core 3.1) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (107ms)  : 105, 108
     .   : milestone, 107,
    master - mean (106ms)  : 105, 107
     .   : milestone, 106,

    section Baseline
    This PR (7420) - mean (105ms)  : 103, 108
     .   : milestone, 105,
    master - mean (105ms)  : 103, 107
     .   : milestone, 105,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (702ms)  : 682, 721
     .   : milestone, 702,
    master - mean (698ms)  : 678, 718
     .   : milestone, 698,
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gantt
    title Execution time (ms) FakeDbCommand (.NET 6) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (94ms)  : 92, 95
     .   : milestone, 94,
    master - mean (94ms)  : 93, 95
     .   : milestone, 94,

    section Baseline
    This PR (7420) - mean (93ms)  : 91, 95
     .   : milestone, 93,
    master - mean (93ms)  : 91, 95
     .   : milestone, 93,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (662ms)  : 642, 682
     .   : milestone, 662,
    master - mean (652ms)  : 635, 669
     .   : milestone, 652,
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gantt
    title Execution time (ms) FakeDbCommand (.NET 8) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (93ms)  : 91, 94
     .   : milestone, 93,
    master - mean (92ms)  : 91, 94
     .   : milestone, 92,

    section Baseline
    This PR (7420) - mean (92ms)  : 89, 95
     .   : milestone, 92,
    master - mean (92ms)  : 90, 94
     .   : milestone, 92,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (595ms)  : 584, 606
     .   : milestone, 595,
    master - mean (595ms)  : 583, 608
     .   : milestone, 595,
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gantt
    title Execution time (ms) HttpMessageHandler (.NET Framework 4.8) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (204ms)  : 199, 210
     .   : milestone, 204,
    master - mean (199ms)  : 194, 204
     .   : milestone, 199,

    section Baseline
    This PR (7420) - mean (196ms)  : 188, 204
     .   : milestone, 196,
    master - mean (197ms)  : 193, 202
     .   : milestone, 197,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (1,129ms)  : 1095, 1162
     .   : milestone, 1129,
    master - mean (1,119ms)  : 1070, 1167
     .   : milestone, 1119,
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gantt
    title Execution time (ms) HttpMessageHandler (.NET Core 3.1) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (282ms)  : 278, 286
     .   : milestone, 282,
    master - mean (286ms)  : 279, 292
     .   : milestone, 286,

    section Baseline
    This PR (7420) - mean (282ms)  : 276, 288
     .   : milestone, 282,
    master - mean (283ms)  : 276, 290
     .   : milestone, 283,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (914ms)  : 882, 946
     .   : milestone, 914,
    master - mean (910ms)  : 877, 943
     .   : milestone, 910,
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gantt
    title Execution time (ms) HttpMessageHandler (.NET 6) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (275ms)  : 270, 279
     .   : milestone, 275,
    master - mean (275ms)  : 270, 280
     .   : milestone, 275,

    section Baseline
    This PR (7420) - mean (275ms)  : 268, 283
     .   : milestone, 275,
    master - mean (275ms)  : 269, 280
     .   : milestone, 275,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (899ms)  : 859, 938
     .   : milestone, 899,
    master - mean (894ms)  : 856, 932
     .   : milestone, 894,
Loading 
gantt
    title Execution time (ms) HttpMessageHandler (.NET 8) 
    dateFormat  X
    axisFormat %s
    todayMarker off
    section Bailout
    This PR (7420) - mean (274ms)  : 269, 279
     .   : milestone, 274,
    master - mean (277ms)  : 272, 282
     .   : milestone, 277,

    section Baseline
    This PR (7420) - mean (272ms)  : 268, 276
     .   : milestone, 272,
    master - mean (275ms)  : 270, 280
     .   : milestone, 275,

    section CallTarget+Inlining+NGEN
    This PR (7420) - mean (812ms)  : 780, 845
     .   : milestone, 812,
    master - mean (812ms)  : 785, 839
     .   : milestone, 812,
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pr-commenter bot commented Aug 20, 2025 •
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Benchmarks

Benchmarks Report for benchmark platform 🐌

Benchmarks for #7420 compared to master:

  • 2 benchmarks are faster, with geometric mean 2.236
  • 1 benchmarks are slower, with geometric mean 1.177
  • 6 benchmarks have fewer allocations
  • 7 benchmarks have more allocations

The following thresholds were used for comparing the benchmark speeds:

  • Mann–Whitney U test with statistical test for significance of 5%
  • Only results indicating a difference greater than 10% and 0.3 ns are considered.

Allocation changes below 0.5% are ignored.

Benchmark details

Benchmarks.Trace.ActivityBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master StartStopWithChild net6.0 10.4μs 58ns 362ns 0 0 0 5.5 KB
master StartStopWithChild netcoreapp3.1 13.6μs 63.5ns 246ns 0 0 0 5.69 KB
master StartStopWithChild net472 22.1μs 120ns 667ns 0.885 0.111 0 6 KB
#7420 StartStopWithChild net6.0 10.2μs 56ns 322ns 0 0 0 5.49 KB
#7420 StartStopWithChild netcoreapp3.1 13.2μs 70.2ns 358ns 0 0 0 5.69 KB
#7420 StartStopWithChild net472 21.8μs 116ns 626ns 0.983 0.437 0.109 5.98 KB
Benchmarks.Trace.AgentWriterBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master WriteAndFlushEnrichedTraces net6.0 932μs 221ns 827ns 0 0 0 2.71 KB
master WriteAndFlushEnrichedTraces netcoreapp3.1 1.02ms 260ns 1.01μs 0 0 0 2.7 KB
master WriteAndFlushEnrichedTraces net472 1.21ms 722ns 2.6μs 0 0 0 3.31 KB
#7420 WriteAndFlushEnrichedTraces net6.0 929μs 146ns 564ns 0 0 0 2.7 KB
#7420 WriteAndFlushEnrichedTraces netcoreapp3.1 1.05ms 392ns 1.47μs 0 0 0 2.7 KB
#7420 WriteAndFlushEnrichedTraces net472 1.22ms 69.5ns 260ns 0 0 0 3.31 KB
Benchmarks.Trace.Asm.AppSecBodyBenchmark - Same speed ✔️ More allocations ⚠️

More allocations ⚠️ in #7420

Benchmark Base Allocated Diff Allocated Change Change %
Benchmarks.Trace.Asm.AppSecBodyBenchmark.AllCycleSimpleBody‑net472 195.46 KB 199.81 KB 4.34 KB 2.22%
Benchmarks.Trace.Asm.AppSecBodyBenchmark.AllCycleMoreComplexBody‑net472 198.98 KB 203.32 KB 4.34 KB 2.18%
Benchmarks.Trace.Asm.AppSecBodyBenchmark.AllCycleSimpleBody‑netcoreapp3.1 174.18 KB 177.77 KB 3.58 KB 2.06%
Benchmarks.Trace.Asm.AppSecBodyBenchmark.AllCycleSimpleBody‑net6.0 172.07 KB 175.6 KB 3.52 KB 2.05%
Benchmarks.Trace.Asm.AppSecBodyBenchmark.AllCycleMoreComplexBody‑netcoreapp3.1 177.6 KB 181.18 KB 3.58 KB 2.02%
Benchmarks.Trace.Asm.AppSecBodyBenchmark.AllCycleMoreComplexBody‑net6.0 175.58 KB 179.1 KB 3.52 KB 2.01%

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master AllCycleSimpleBody net6.0 325μs 1.43μs 5.53μs 0 0 0 172.07 KB
master AllCycleSimpleBody netcoreapp3.1 461μs 1.27μs 4.93μs 0 0 0 174.18 KB
master AllCycleSimpleBody net472 430μs 124ns 445ns 30.2 0 0 195.46 KB
master AllCycleMoreComplexBody net6.0 329μs 105ns 392ns 0 0 0 175.58 KB
master AllCycleMoreComplexBody netcoreapp3.1 502μs 318ns 1.23μs 0 0 0 177.6 KB
master AllCycleMoreComplexBody net472 437μs 106ns 398ns 30.2 0 0 198.98 KB
master ObjectExtractorSimpleBody net6.0 323ns 0.146ns 0.547ns 0 0 0 280 B
master ObjectExtractorSimpleBody netcoreapp3.1 420ns 2.37ns 15.7ns 0 0 0 272 B
master ObjectExtractorSimpleBody net472 299ns 0.0328ns 0.123ns 0.0436 0 0 281 B
master ObjectExtractorMoreComplexBody net6.0 6.36μs 32.9ns 171ns 0 0 0 3.78 KB
master ObjectExtractorMoreComplexBody netcoreapp3.1 7.82μs 15.8ns 61.1ns 0 0 0 3.69 KB
master ObjectExtractorMoreComplexBody net472 6.75μs 4.47ns 17.3ns 0.572 0 0 3.8 KB
#7420 AllCycleSimpleBody net6.0 333μs 190ns 735ns 0 0 0 175.6 KB
#7420 AllCycleSimpleBody netcoreapp3.1 488μs 639ns 2.47μs 0 0 0 177.77 KB
#7420 AllCycleSimpleBody net472 444μs 205ns 768ns 30.2 0 0 199.81 KB
#7420 AllCycleMoreComplexBody net6.0 337μs 288ns 1.04μs 0 0 0 179.1 KB
#7420 AllCycleMoreComplexBody netcoreapp3.1 509μs 1.34μs 5.19μs 0 0 0 181.18 KB
#7420 AllCycleMoreComplexBody net472 454μs 218ns 816ns 31.2 0 0 203.32 KB
#7420 ObjectExtractorSimpleBody net6.0 328ns 0.332ns 1.29ns 0 0 0 280 B
#7420 ObjectExtractorSimpleBody netcoreapp3.1 400ns 1.95ns 8.29ns 0 0 0 272 B
#7420 ObjectExtractorSimpleBody net472 301ns 0.034ns 0.131ns 0.0439 0 0 281 B
#7420 ObjectExtractorMoreComplexBody net6.0 6.28μs 13.9ns 53.9ns 0 0 0 3.78 KB
#7420 ObjectExtractorMoreComplexBody netcoreapp3.1 7.66μs 34.7ns 134ns 0 0 0 3.69 KB
#7420 ObjectExtractorMoreComplexBody net472 6.69μs 5.13ns 19.9ns 0.601 0 0 3.8 KB
Benchmarks.Trace.Asm.AppSecEncoderBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master EncodeArgs net6.0 76.4μs 173ns 669ns 0 0 0 32.4 KB
master EncodeArgs netcoreapp3.1 95.6μs 279ns 1.08μs 0 0 0 32.4 KB
master EncodeArgs net472 117μs 9.04ns 35ns 4.69 0 0 32.51 KB
master EncodeLegacyArgs net6.0 143μs 25.5ns 95.3ns 0 0 0 2.15 KB
master EncodeLegacyArgs netcoreapp3.1 198μs 215ns 831ns 0 0 0 2.14 KB
master EncodeLegacyArgs net472 263μs 183ns 710ns 0 0 0 2.16 KB
#7420 EncodeArgs net6.0 78.1μs 168ns 649ns 0 0 0 32.4 KB
#7420 EncodeArgs netcoreapp3.1 96.8μs 302ns 1.17μs 0 0 0 32.4 KB
#7420 EncodeArgs net472 109μs 8.77ns 31.6ns 4.89 0 0 32.51 KB
#7420 EncodeLegacyArgs net6.0 146μs 25.9ns 93.5ns 0 0 0 2.14 KB
#7420 EncodeLegacyArgs netcoreapp3.1 198μs 192ns 745ns 0 0 0 2.14 KB
#7420 EncodeLegacyArgs net472 262μs 34.3ns 133ns 0 0 0 2.16 KB
Benchmarks.Trace.Asm.AppSecWafBenchmark - Faster 🎉 Same allocations ✔️

Faster 🎉 in #7420

Benchmark base/diff Base Median (ns) Diff Median (ns) Modality
Benchmarks.Trace.Asm.AppSecWafBenchmark.RunWafRealisticBenchmarkWithAttack‑netcoreapp3.1 2.441 731,759.45 299,805.51
Benchmarks.Trace.Asm.AppSecWafBenchmark.RunWafRealisticBenchmark‑netcoreapp3.1 2.049 858,787.30 419,153.75

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master RunWafRealisticBenchmark net6.0 396μs 100ns 376ns 0 0 0 4.55 KB
master RunWafRealisticBenchmark netcoreapp3.1 800μs 14μs 140μs 0 0 0 4.48 KB
master RunWafRealisticBenchmark net472 431μs 66.3ns 257ns 0 0 0 4.66 KB
master RunWafRealisticBenchmarkWithAttack net6.0 295μs 79.1ns 306ns 0 0 0 2.24 KB
master RunWafRealisticBenchmarkWithAttack netcoreapp3.1 691μs 9.27μs 92.7μs 0 0 0 2.22 KB
master RunWafRealisticBenchmarkWithAttack net472 312μs 70.5ns 273ns 0 0 0 2.29 KB
#7420 RunWafRealisticBenchmark net6.0 403μs 84.7ns 317ns 0 0 0 4.56 KB
#7420 RunWafRealisticBenchmark netcoreapp3.1 419μs 136ns 470ns 0 0 0 4.48 KB
#7420 RunWafRealisticBenchmark net472 437μs 43ns 166ns 0 0 0 4.66 KB
#7420 RunWafRealisticBenchmarkWithAttack net6.0 294μs 42.6ns 165ns 0 0 0 2.24 KB
#7420 RunWafRealisticBenchmarkWithAttack netcoreapp3.1 300μs 202ns 756ns 0 0 0 2.22 KB
#7420 RunWafRealisticBenchmarkWithAttack net472 316μs 69.8ns 270ns 0 0 0 2.29 KB
Benchmarks.Trace.AspNetCoreBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master SendRequest net6.0 62μs 33.2ns 124ns 0 0 0 14.52 KB
master SendRequest netcoreapp3.1 70.3μs 170ns 636ns 0 0 0 17.42 KB
master SendRequest net472 0.00994ns 0.00342ns 0.0133ns 0 0 0 0 b
#7420 SendRequest net6.0 60.3μs 23.8ns 82.5ns 0 0 0 14.52 KB
#7420 SendRequest netcoreapp3.1 72.6μs 89ns 345ns 0 0 0 17.42 KB
#7420 SendRequest net472 0.00876ns 0.00168ns 0.00651ns 0 0 0 0 b
Benchmarks.Trace.CharSliceBenchmark - Slower ⚠️ Fewer allocations 🎉

Slower ⚠️ in #7420

Benchmark diff/base Base Median (ns) Diff Median (ns) Modality
Benchmarks.Trace.CharSliceBenchmark.OriginalCharSlice‑netcoreapp3.1 1.177 2,108,410.16 2,482,366.88

Fewer allocations 🎉 in #7420

Benchmark Base Allocated Diff Allocated Change Change %
Benchmarks.Trace.CharSliceBenchmark.OptimizedCharSlice‑net6.0 7 B 2 B -5 B -71.43%
Benchmarks.Trace.CharSliceBenchmark.OptimizedCharSliceWithPool‑net6.0 4 B 1 B -3 B -75.00%

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master OriginalCharSlice net6.0 1.95ms 431ns 1.67μs 0 0 0 640.01 KB
master OriginalCharSlice netcoreapp3.1 2.13ms 9.42μs 36.5μs 0 0 0 640 KB
master OriginalCharSlice net472 2.62ms 784ns 2.93μs 100 0 0 641.95 KB
master OptimizedCharSlice net6.0 1.37ms 188ns 726ns 0 0 0 7 B
master OptimizedCharSlice netcoreapp3.1 1.67ms 354ns 1.37μs 0 0 0 1 B
master OptimizedCharSlice net472 1.98ms 606ns 2.35μs 0 0 0 0 b
master OptimizedCharSliceWithPool net6.0 823μs 48.6ns 188ns 0 0 0 4 B
master OptimizedCharSliceWithPool netcoreapp3.1 833μs 56.8ns 213ns 0 0 0 0 b
master OptimizedCharSliceWithPool net472 1.15ms 49.5ns 192ns 0 0 0 0 b
#7420 OriginalCharSlice net6.0 1.93ms 615ns 2.3μs 0 0 0 640.01 KB
#7420 OriginalCharSlice netcoreapp3.1 2.48ms 4.55μs 17μs 0 0 0 640 KB
#7420 OriginalCharSlice net472 2.67ms 1.38μs 4.97μs 100 0 0 641.95 KB
#7420 OptimizedCharSlice net6.0 1.36ms 368ns 1.43μs 0 0 0 2 B
#7420 OptimizedCharSlice netcoreapp3.1 1.67ms 332ns 1.24μs 0 0 0 1 B
#7420 OptimizedCharSlice net472 1.93ms 434ns 1.68μs 0 0 0 0 b
#7420 OptimizedCharSliceWithPool net6.0 795μs 34.3ns 133ns 0 0 0 1 B
#7420 OptimizedCharSliceWithPool netcoreapp3.1 840μs 90.1ns 337ns 0 0 0 0 b
#7420 OptimizedCharSliceWithPool net472 1.16ms 40ns 150ns 0 0 0 0 b
Benchmarks.Trace.CIVisibilityProtocolWriterBenchmark - Same speed ✔️ Fewer allocations 🎉

Fewer allocations 🎉 in #7420

Benchmark Base Allocated Diff Allocated Change Change %
Benchmarks.Trace.CIVisibilityProtocolWriterBenchmark.WriteAndFlushEnrichedTraces‑net472 56.46 KB 56.15 KB -307 B -0.54%

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master WriteAndFlushEnrichedTraces net6.0 728μs 3.63μs 15.4μs 0 0 0 41.59 KB
master WriteAndFlushEnrichedTraces netcoreapp3.1 672μs 3.76μs 26.6μs 0 0 0 42.08 KB
master WriteAndFlushEnrichedTraces net472 877μs 1.65μs 6.16μs 8.33 0 0 56.46 KB
#7420 WriteAndFlushEnrichedTraces net6.0 719μs 961ns 3.72μs 0 0 0 41.78 KB
#7420 WriteAndFlushEnrichedTraces netcoreapp3.1 651μs 3.02μs 19.8μs 0 0 0 41.92 KB
#7420 WriteAndFlushEnrichedTraces net472 896μs 3.37μs 13.1μs 8.33 0 0 56.15 KB
Benchmarks.Trace.DbCommandBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master ExecuteNonQuery net6.0 1.89μs 5.82ns 21.8ns 0 0 0 1.02 KB
master ExecuteNonQuery netcoreapp3.1 2.48μs 10.4ns 39ns 0 0 0 1.02 KB
master ExecuteNonQuery net472 2.92μs 5.69ns 22ns 0.144 0.0144 0 987 B
#7420 ExecuteNonQuery net6.0 1.9μs 2.98ns 11.6ns 0 0 0 1.02 KB
#7420 ExecuteNonQuery netcoreapp3.1 2.5μs 10.4ns 36.1ns 0 0 0 1.02 KB
#7420 ExecuteNonQuery net472 2.8μs 3.22ns 12.5ns 0.152 0.0138 0 987 B
Benchmarks.Trace.ElasticsearchBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master CallElasticsearch net6.0 1.73μs 8.8ns 39.4ns 0 0 0 1.03 KB
master CallElasticsearch netcoreapp3.1 2.25μs 10.6ns 41.2ns 0 0 0 1.03 KB
master CallElasticsearch net472 3.63μs 1.45ns 5.43ns 0.163 0 0 1.04 KB
master CallElasticsearchAsync net6.0 1.85μs 6.28ns 22.6ns 0 0 0 1.01 KB
master CallElasticsearchAsync netcoreapp3.1 2.34μs 8.78ns 32.9ns 0 0 0 1.08 KB
master CallElasticsearchAsync net472 3.85μs 4.25ns 16.5ns 0.172 0 0 1.1 KB
#7420 CallElasticsearch net6.0 1.79μs 5.98ns 23.2ns 0 0 0 1.03 KB
#7420 CallElasticsearch netcoreapp3.1 2.27μs 11.4ns 44.3ns 0 0 0 1.03 KB
#7420 CallElasticsearch net472 3.65μs 4.07ns 15.8ns 0.164 0 0 1.04 KB
#7420 CallElasticsearchAsync net6.0 1.77μs 8.34ns 31.2ns 0 0 0 1.01 KB
#7420 CallElasticsearchAsync netcoreapp3.1 2.42μs 9.79ns 37.9ns 0 0 0 1.08 KB
#7420 CallElasticsearchAsync net472 3.71μs 4.26ns 16.5ns 0.167 0 0 1.1 KB
Benchmarks.Trace.GraphQLBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master ExecuteAsync net6.0 1.86μs 1.44ns 5.39ns 0 0 0 952 B
master ExecuteAsync netcoreapp3.1 2.28μs 7.72ns 29.9ns 0 0 0 952 B
master ExecuteAsync net472 2.61μs 1ns 3.89ns 0.144 0 0 915 B
#7420 ExecuteAsync net6.0 1.87μs 9.79ns 45.9ns 0 0 0 953 B
#7420 ExecuteAsync netcoreapp3.1 2.29μs 7.17ns 27.8ns 0 0 0 952 B
#7420 ExecuteAsync net472 2.6μs 1.05ns 4.07ns 0.143 0 0 915 B
Benchmarks.Trace.HttpClientBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master SendAsync net6.0 7.13μs 15ns 58.2ns 0 0 0 2.36 KB
master SendAsync netcoreapp3.1 8.3μs 30.9ns 120ns 0 0 0 2.9 KB
master SendAsync net472 12.5μs 10.4ns 40.4ns 0.503 0 0 3.18 KB
#7420 SendAsync net6.0 6.97μs 13.3ns 51.4ns 0 0 0 2.36 KB
#7420 SendAsync netcoreapp3.1 8.53μs 17.6ns 68.2ns 0 0 0 2.9 KB
#7420 SendAsync net472 12.5μs 7.9ns 30.6ns 0.499 0 0 3.18 KB
Benchmarks.Trace.Iast.StringAspectsBenchmark - Same speed ✔️ More allocations ⚠️

More allocations ⚠️ in #7420

Benchmark Base Allocated Diff Allocated Change Change %
Benchmarks.Trace.Iast.StringAspectsBenchmark.StringConcatAspectBenchmark‑net6.0 259.42 KB 278.42 KB 18.99 KB 7.32%

Fewer allocations 🎉 in #7420

Benchmark Base Allocated Diff Allocated Change Change %
Benchmarks.Trace.Iast.StringAspectsBenchmark.StringConcatBenchmark‑net6.0 44.61 KB 43.73 KB -880 B -1.97%
Benchmarks.Trace.Iast.StringAspectsBenchmark.StringConcatAspectBenchmark‑netcoreapp3.1 277.95 KB 248.51 KB -29.44 KB -10.59%
Benchmarks.Trace.Iast.StringAspectsBenchmark.StringConcatBenchmark‑net472 65.54 KB 57.34 KB -8.19 KB -12.50%

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master StringConcatBenchmark net6.0 52.3μs 693ns 6.89μs 0 0 0 44.61 KB
master StringConcatBenchmark netcoreapp3.1 56μs 775ns 7.67μs 0 0 0 43.04 KB
master StringConcatBenchmark net472 57.2μs 241ns 934ns 0 0 0 65.54 KB
master StringConcatAspectBenchmark net6.0 449μs 1.6μs 5.55μs 0 0 0 259.42 KB
master StringConcatAspectBenchmark netcoreapp3.1 512μs 1.88μs 6.52μs 0 0 0 277.95 KB
master StringConcatAspectBenchmark net472 403μs 2.2μs 13μs 0 0 0 278.53 KB
#7420 StringConcatBenchmark net6.0 48.9μs 269ns 1.57μs 0 0 0 43.73 KB
#7420 StringConcatBenchmark netcoreapp3.1 48.4μs 232ns 1.83μs 0 0 0 43.05 KB
#7420 StringConcatBenchmark net472 57.4μs 286ns 1.31μs 0 0 0 57.34 KB
#7420 StringConcatAspectBenchmark net6.0 487μs 952ns 4.76μs 0 0 0 278.42 KB
#7420 StringConcatAspectBenchmark netcoreapp3.1 490μs 2.11μs 7.9μs 0 0 0 248.51 KB
#7420 StringConcatAspectBenchmark net472 405μs 2.33μs 18.7μs 0 0 0 278.53 KB
Benchmarks.Trace.ILoggerBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master EnrichedLog net6.0 2.58μs 12.2ns 50.2ns 0 0 0 1.7 KB
master EnrichedLog netcoreapp3.1 3.42μs 1.49ns 5.59ns 0 0 0 1.7 KB
master EnrichedLog net472 4.09μs 5.8ns 22.5ns 0.244 0 0 1.64 KB
#7420 EnrichedLog net6.0 2.62μs 1.39ns 5.19ns 0 0 0 1.7 KB
#7420 EnrichedLog netcoreapp3.1 3.48μs 17.9ns 81.8ns 0 0 0 1.7 KB
#7420 EnrichedLog net472 3.97μs 4.14ns 16ns 0.257 0 0 1.64 KB
Benchmarks.Trace.Log4netBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master EnrichedLog net6.0 124μs 159ns 575ns 0 0 0 4.31 KB
master EnrichedLog netcoreapp3.1 127μs 165ns 594ns 0 0 0 4.31 KB
master EnrichedLog net472 167μs 30.3ns 114ns 0 0 0 4.52 KB
#7420 EnrichedLog net6.0 122μs 49.3ns 184ns 0 0 0 4.31 KB
#7420 EnrichedLog netcoreapp3.1 128μs 198ns 715ns 0 0 0 4.31 KB
#7420 EnrichedLog net472 168μs 69.8ns 252ns 0 0 0 4.52 KB
Benchmarks.Trace.NLogBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master EnrichedLog net6.0 5.03μs 14.3ns 55.4ns 0 0 0 2.26 KB
master EnrichedLog netcoreapp3.1 6.65μs 15.2ns 58.8ns 0 0 0 2.26 KB
master EnrichedLog net472 7.43μs 10ns 38.8ns 0.296 0 0 2.08 KB
#7420 EnrichedLog net6.0 5.21μs 11.8ns 44ns 0 0 0 2.26 KB
#7420 EnrichedLog netcoreapp3.1 6.78μs 5.69ns 21.3ns 0 0 0 2.26 KB
#7420 EnrichedLog net472 7.63μs 11ns 42.7ns 0.304 0 0 2.08 KB
Benchmarks.Trace.RedisBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master SendReceive net6.0 1.98μs 6.17ns 23.9ns 0 0 0 1.2 KB
master SendReceive netcoreapp3.1 2.57μs 13.1ns 58.5ns 0 0 0 1.2 KB
master SendReceive net472 3.17μs 2.09ns 8.1ns 0.19 0 0 1.2 KB
#7420 SendReceive net6.0 1.98μs 9.04ns 36.2ns 0 0 0 1.2 KB
#7420 SendReceive netcoreapp3.1 2.64μs 3.91ns 15.1ns 0 0 0 1.2 KB
#7420 SendReceive net472 3.26μs 3.3ns 12.8ns 0.177 0 0 1.2 KB
Benchmarks.Trace.SerilogBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master EnrichedLog net6.0 4.15μs 5.83ns 22.6ns 0 0 0 1.58 KB
master EnrichedLog netcoreapp3.1 5.95μs 13.2ns 51ns 0 0 0 1.63 KB
master EnrichedLog net472 6.88μs 9.54ns 37ns 0.312 0 0 2.03 KB
#7420 EnrichedLog net6.0 4.11μs 1.81ns 7ns 0 0 0 1.58 KB
#7420 EnrichedLog netcoreapp3.1 5.55μs 15.7ns 60.6ns 0 0 0 1.63 KB
#7420 EnrichedLog net472 6.8μs 4.82ns 18ns 0.309 0 0 2.03 KB
Benchmarks.Trace.SpanBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master StartFinishSpan net6.0 744ns 3.76ns 16.4ns 0 0 0 576 B
master StartFinishSpan netcoreapp3.1 946ns 4.47ns 17.9ns 0 0 0 576 B
master StartFinishSpan net472 894ns 0.243ns 0.91ns 0.0916 0 0 578 B
master StartFinishScope net6.0 923ns 4.59ns 20ns 0 0 0 696 B
master StartFinishScope netcoreapp3.1 1.11μs 5.37ns 21.5ns 0 0 0 696 B
master StartFinishScope net472 1.11μs 0.248ns 0.962ns 0.0996 0 0 658 B
#7420 StartFinishSpan net6.0 734ns 2.7ns 10.5ns 0 0 0 576 B
#7420 StartFinishSpan netcoreapp3.1 942ns 3.83ns 16.7ns 0 0 0 576 B
#7420 StartFinishSpan net472 902ns 0.627ns 2.35ns 0.0895 0 0 578 B
#7420 StartFinishScope net6.0 879ns 4.72ns 24.1ns 0 0 0 696 B
#7420 StartFinishScope netcoreapp3.1 1.18μs 6.29ns 32.7ns 0 0 0 696 B
#7420 StartFinishScope net472 1.1μs 2.2ns 8.5ns 0.103 0 0 658 B
Benchmarks.Trace.TraceAnnotationsBenchmark - Same speed ✔️ Same allocations ✔️

Raw results

Branch Method Toolchain Mean StdError StdDev Gen 0 Gen 1 Gen 2 Allocated
master RunOnMethodBegin net6.0 1.05μs 5.09ns 20.4ns 0 0 0 696 B
master RunOnMethodBegin netcoreapp3.1 1.36μs 6.47ns 25.1ns 0 0 0 696 B
master RunOnMethodBegin net472 1.38μs 0.233ns 0.902ns 0.0979 0 0 658 B
#7420 RunOnMethodBegin net6.0 1.01μs 5.22ns 24.5ns 0 0 0 697 B
#7420 RunOnMethodBegin netcoreapp3.1 1.39μs 7.18ns 33.7ns 0 0 0 696 B
#7420 RunOnMethodBegin net472 1.4μs 1.92ns 7.43ns 0.104 0 0 658 B

This was referenced Aug 20, 2025
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andrewlock
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Nice, some great documentation for the public APIs 👍 Most of the comments are just tiny nits, but there's some things we'll need to address with the ordering in the telemetry I think

zacharycmontoya
zacharycmontoya reviewed Aug 20, 2025
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andrewlock added a commit that referenced this pull request Aug 21, 2025
@andrewlock
More ConfigurationBuilder refactoring to avoid incorrect usages (#7422
f25da88 
)

## Summary of changes

- Fix `ClassConfigurationResultWithKey.WithDefault()` to take a
`DefaultResult<T>`
- Don't allow creating arbitrary `StructConfigurationResultWithKey`
- Remove (inline) buggy `RecordTelemetry<>` method

## Reason for change

When reviewing #7420, I
noticed there was an incorrect usage of `WithDefault()` due to
limitations in the type system, so this tries to close that gap.
Unfortunately, that required more changes than I would like, due to
limitations in generics and constraints.

## Implementation details

- Inline the `RecordTelemetry<T>` method
- Explicitly limit the types of `StructConfigurationResultWithKey<T>`
that may be created by using static factory methods and a `private` ctor
- Fix `ClassConfigurationResultWithKey.WithDefault()` to take a
`DefaultResult<T>` so that we always have a telemetry value to record.
This will be slightly clunky if you try to do it with `string`, but we
can close that gap later if we need to

## Test coverage

Added a couple of small unit tests

## Other details

Spotted when reviewing

- #7420


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andrewlock added a commit that referenced this pull request Aug 21, 2025
@andrewlock
Add missing GetDictionary() method to ConfigurationBuilder (#7421)
d2b282b 
## Summary of changes

Add missing `GetDictionary()` method to `ConfigurationBuilder`

## Reason for change

We were missing a method that allows providing a default instance for a
dictionary up-front. This was forcing using other overloads that are
suboptimal for telemetry.

## Implementation details

Add the missing helper that allows providing a default value. I allowed
passing a null value in here, as it avoids unnecessary allocations if
you don't actually need the dictionary. A good example was the fixed
usage in `InitializeHeaderTags` which was creating an empty dictionary
instead of taking the fast-path `null` route (and potentially actually
giving _incorrect_ settings in the `DynamicSettings` I think

## Test coverage

Meh

## Other details

Spotted when reviewing
- #7420


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link04
link04 commented Sep 5, 2025
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zacharycmontoya
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I have one blocking concern with the weird interaction between OTEL_METRICS_EXPORTER and the runtime metrics config. Otherwise, just left some comments for smaller tweaks

@link04
Applying nits and updating tests
cd45d81 
Applying nits and updating tests
@link04 link04 force-pushed the maximo/otel-metrics-api-configs branch from f571fb5 to cd45d81 Compare September 5, 2025 20:14
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✅ Tests

🎉 All green!

❄️ No new flaky tests detected
🧪 All tests passed

This comment will be updated automatically if new data arrives.
🔗 Commit SHA: e3f9af2 | Docs | Was this helpful? Give us feedback!

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After the configuration changes, it looks like we're reporting the correct default values and setting runtime metrics enabled correctly. Thanks for following up on all the feedback!

@link04 link04 merged commit 7b1530f into master Sep 10, 2025
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@link04 link04 deleted the maximo/otel-metrics-api-configs branch September 10, 2025 14:07
@github-actions github-actions bot added this to the vNext-v3 milestone Sep 10, 2025
This was referenced Sep 13, 2025
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@link04 link04 added the area:opentelemetry OpenTelemetry support label Sep 13, 2025
link04 added a commit that referenced this pull request Sep 26, 2025
@link04
[OTEL] Metrics API Support - Collection Implementation (#7511)
bad5402 
## Summary of changes
This PR implements the metrics collection foundation for OpenTelemetry
Metrics API supportKey additions include:

- MetricReader: Component for collecting instrument measurements and
aggregating them
- MetricReaderHandler: High-performance measurement processing with
proper aggregation (Sum, Last Value, Histogram)
- MetricPoint: Thread-safe data structure for metric aggregation with
histogram bucket support
- Testing: Unit test covering all 7 instrument types (4 sync + 3 async)
with exact OTLP value verification

This is the second of a series of 3 PRs to complete the OpenTelemetry
Metrics API support.
1. [[OTEL] Metrics API Support - Configurations & Telemetry
#7420](#7420)
2. [[OTEL] Metrics API Support - Collection Implementation
#7511](#7511) <- You are
here.
3. [[OTEL] Metrics API Support - Metrics Reader & OTLP Exporter
#7514](#7514)


## Reason for change
The [RFC] OpenTelemetry Metrics API support requires implementing
metrics collection that's compatible with the OpenTelemetry data model.
This PR provides the collection foundation that will enable customers to
use .NET's `System.Diagnostics.Metrics` API with Datadog as a drop-in
replacement for the OpenTelemetry SDK.

Business Impact: Enables the collection phase of OpenTelemetry Metrics
API support, laying the groundwork for OTLP export in the next PR.

## Implementation details
✅ Metrics Collection Components:
- MetricReader - RFC-compliant component for initialization and async
collection
- MetricReaderHandler - Measurement processing and aggregation
- MetricPoint - Aggregation data structure with histogram bucket support

✅ Aggregation Mapping:
- Counter/Asynchronous Counter → Sum Aggregation → Sum Metric Point ✅
- UpDownCounter/Asynchronous UpDownCounter → Sum Aggregation → Sum
Metric Point ✅
- Gauge/Asynchronous Gauge → Last Value Aggregation → Gauge Metric Point
✅
- Histogram → Explicit Bucket Histogram Aggregation → Histogram Metric
Point ✅

## Test coverage
Added unit test `MeterListenerCapturesAllMetrics()` that verifies:
- All 7 instrument types (Counter, Histogram, Gauge, UpDownCounter + 3
Async variants)
- Value verification matching OTLP snapshot expectations
Histogram bucket logic verification
- Sync + Async instrument collection
- Tag capture and temporality settings

## Other details
Jira: [APMAPI-1572](https://datadoghq.atlassian.net/browse/APMAPI-1572)

<!-- Fixes #{issue} -->

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[APMAPI-1572]:
https://datadoghq.atlassian.net/browse/APMAPI-1572?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ
link04 added a commit that referenced this pull request Oct 7, 2025
@link04
[OTEL] Metrics API Support - Metrics Reader & OTLP Exporter (#7514)
33b6106 
## Summary of changes
This PR implements the OTLP Metrics Exporter for OpenTelemetry Metrics
API support, completing the final piece of the RFC implementation. Key
additions include:
- OTLP Metrics Exporter: Implemented `MetricExporter` abstract class and
`OtlpExporter` concrete implementation initially with only `
HTTP/protobuf` transport support ATM.
- Performance Optimizations: Custom protobuf serialization without
external dependencies, async operations with ConfigureAwait(false)
- Retry Logic: Exponential backoff with Retry-After header handling for
HTTP 429, 502, 503, 504 responses
- Telemetry Metrics: Internal metrics tracking
(`metrics_export_attempts`, `metrics_export_successes`,
`metrics_export_failures`) with protocol tag
- Sample App Integration: Enhanced Samples.OpenTelemetrySdk to support
both DD and OTel SDK approaches for comparative snapshot testing

This completes the series of 3 PRs for OpenTelemetry Metrics API
support.
1. [[OTEL] Metrics API Support - Configurations & Telemetry
#7420](#7420)
2. [[OTEL] Metrics API Support - Collection Implementation
#7511](#7511)
3. [[OTEL] Metrics API Support - Metrics Reader & OTLP Exporter
#7514](#7514) <- You are
here.

## Reason for change
The [RFC] OpenTelemetry Metrics API support requires the .NET tracer to
act as a drop-in replacement for the OpenTelemetry SDK. This PR
implements the OTLP export functionality, enabling customers to migrate
from OTel SDK to Datadog SDK with zero friction.
Business Impact: Enables customers using OpenTelemetry Metrics API to
switch to Datadog without code changes, supporting our strategic
initiative to be OTel-native.

## Implementation details
:white_check_mark: OTLP Metrics Exporter Components:
- MetricExporter - Abstract base class defining export contract
- OtlpExporter - Concrete implementation with HTTP/protobuf transport
- OtlpMetricsSerializer - Custom protobuf serialization for performance
- MetricReader - Updated to use the new exporter architecture

:white_check_mark: Key Features:
- HTTP/protobuf transport support
- Resource attribute precedence following RFC (DD_* → OTEL_* → defaults)
- Retry logic with exponential backoff and proper HTTP status handling
- Telemetry metrics with protocol tags (protocol:http/protobuf,
protocol:grpc, protocol:http/json)
- Performance optimizations with async operations and custom
serialization

:white_check_mark: Sample App Enhancements:
- Conditional OTel SDK exporter via OTEL_METRICS_EXPORTER_ENABLED
environment variable for testing
- Comparative testing between DD and OTel SDK approaches
- Proper MeterProvider lifecycle management with disposal

## Test coverage
Added comprehensive integration test `SubmitsOtlpMetrics` that:
- Tests both approaches: DD enabled/OTel disabled vs DD disabled/OTel
enabled
- Verifies identical results: Both approaches produce the same OTLP
metric requests
- Cross-version testing: Runs across all OpenTelemetry package versions
- Snapshot verification: Ensures RFC compliance and data model
compatibility

**NOTE**: Hoping to add Grpc and HTTP/Json tests along with the current
`SubmitsOtlpMetrics` protobuf one and also benchmarks if possible to
compare OTEL vs Datadog overhead.

## Other details
<!-- Fixes #{issue} -->
Jira: [APMAPI-1573](https://datadoghq.atlassian.net/browse/APMAPI-1573) 

<!--  ⚠️ Note:
Where possible, please obtain 2 approvals prior to merging. Unless
CODEOWNERS specifies otherwise, for external teams it is typically best
to have one review from a team member, and one review from apm-dotnet.
Trivial changes do not require 2 reviews.

MergeQueue is NOT enabled in this repository. If you have write access
to the repo, the PR has 1-2 approvals (see above), and all of the
required checks have passed, you can use the Squash and Merge button to
merge the PR. If you don't have write access, or you need help, reach
out in the #apm-dotnet channel in Slack.
-->


[APMAPI-1573]:
https://datadoghq.atlassian.net/browse/APMAPI-1573?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ
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