[AGNTLOG-468] chore(datadog): add trace sampling #1110

andrewqian2001datadog · 2026-01-20T15:21:26Z

Summary

This PR adds sampling (probalistic, error) for OTLP traces that match the agent's behavior.

In the agent, the priority sampler, and the error sampler is enabled by default

code showing that TargetTps and ErrorTps are set to non zero values

Change Type

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

How did you test this PR?

Correctness tests, manual testing.

build adp and run with sampling enabled.

DD_DATA_PLANE_OTLP_ENABLED=true \
        DD_DATA_PLANE_OTLP_PROXY_ENABLED=false \
        DD_OTLP_CONFIG='{}' \
        DD_APM_CONFIG__PROBABILISTIC_SAMPLER__ENABLED=true \
        DD_APM_CONFIG__PROBABILISTIC_SAMPLER__SAMPLING_PERCENTAGE=50 \
        RUST_LOG=info \
        make run-adp-standalone

Send traces, verify that around ~DD_APM_CONFIG__PROBABILISTIC_SAMPLER__SAMPLING_PERCENTAGE are missing from the trace explorer.

TIME_NS=$(python3 - <<'PY'
import time
print(time.time_ns())
PY
)
END_NS=$((TIME_NS + 1_000_000))
TRACE_ID_B64=$(python3 - <<'PY'
import os,base64
print(base64.b64encode(os.urandom(16)).decode())
PY
)
SPAN_ID_B64=$(python3 - <<'PY'
import os,base64
print(base64.b64encode(os.urandom(8)).decode())
PY
)
grpcurl -plaintext \
  -import-path /Users/andrew.qian/Documents/Code/agent-related/saluki/lib/protos/otlp/proto \
  -proto opentelemetry/proto/collector/trace/v1/trace_service.proto \
  -d @ 127.0.0.1:4317 \
  opentelemetry.proto.collector.trace.v1.TraceService/Export <<JSON
{
  "resourceSpans": [{
    "resource": {
      "attributes": [
        { "key": "service.name", "value": { "stringValue": "saluki-adp" } },
        { "key": "deployment.environment", "value": { "stringValue": "wacktest" } },
        { "key": "host.name", "value": { "stringValue": "COMP-JGW6V7JHF1" } }
      ]
    },
    "scopeSpans": [{
      "scope": { "name": "test-client", "version": "0.1.0" },
      "spans": [{
        "traceId": "$TRACE_ID_B64",
        "spanId": "$SPAN_ID_B64",
        "name": "test-span",
        "kind": 1,
        "startTimeUnixNano": "$TIME_NS",
        "endTimeUnixNano": "$END_NS",
        "attributes": [
          { "key": "env", "value": { "stringValue": "wacktest4" } },
          { "key": "operation.name", "value": { "stringValue": "adp.test" } },
          { "key": "resource.name", "value": { "stringValue": "GET /api" } },
          { "key": "span.type", "value": { "stringValue": "web" } },
          { "key": "sampling.priority", "value": { "intValue": 2 } },
          { "key": "test.run", "value": { "stringValue": "adp-otlp-2" } },
          { "key": "http.method", "value": { "stringValue": "GET" } },
          { "key": "http.url", "value": { "stringValue": "https://example.com/api" } },
          { "key": "http.status_code", "value": { "intValue": 200 } }
        ],
        "status": { "code": 1 }
      }]
    }]
  }]
}
JSON

View the trace explorer (link). I use the env "wacktest4" to filter for my spans, and for some reason the live explorer is not working for me but idk.

References

pr-commenter · 2026-01-20T15:27:06Z

Binary Size Analysis (Agent Data Plane)

Target: be34af7 (baseline) vs b0ba6d8 (comparison) diff
Analysis Type: Stripped binaries (debug symbols excluded)
Baseline Size: 27.54 MiB
Comparison Size: 27.63 MiB
Size Change: +89.62 KiB (+0.32%)
Pass/Fail Threshold: +5%
Result: PASSED ✅

Changes by Module

Module	File Size	Symbols
saluki_components::transforms::trace_sampler	+35.11 KiB	23
core	+31.12 KiB	66
hashbrown	+9.00 KiB	7
saluki_core::data_model::event	+5.95 KiB	7
ZN76<saluki_core	-5.72 KiB	2
[sections]	+3.64 KiB	7
serde_core	+2.12 KiB	8
saluki_components::common::datadog	+1.87 KiB	17
saluki_components::common::otlp	+1.44 KiB	2
saluki_core::topology::blueprint	+1.27 KiB	1
saluki_config::GenericConfiguration::try_get_typed	+1.23 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.10093	+1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.10090	-1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.8479	+1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.8784	+1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.9054	+1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.8476	-1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.8781	-1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.9051	-1.10 KiB	1
_ZN4http6header4name14StandardHeader6as_str17hb45bedc01a2a74c0E.10812	+1.10 KiB	1

Detailed Symbol Changes

    FILE SIZE        VM SIZE    
 --------------  -------------- 
  +3.6% +69.7Ki  +4.1% +60.9Ki    [630 Others]
  [NEW] +27.3Ki  [NEW] +27.2Ki    saluki_components::transforms::apm_stats::ApmStats::process_trace::hea01e15f0321d337
  [NEW] +20.4Ki  [NEW] +20.3Ki    saluki_components::encoders::datadog::traces::TraceEndpointEncoder::encode_tracer_payload::h8e94d45f42e4f777
  [NEW] +14.8Ki  [NEW] +14.6Ki    _<saluki_components::transforms::trace_sampler::TraceSampler as saluki_core::components::transforms::Transform>::run::_{{closure}}::h85b5a4b8d8f03e25
  [NEW] +13.9Ki  [NEW] +13.7Ki    _<core::marker::PhantomData<T> as serde_core::de::DeserializeSeed>::deserialize::h9e9260c51df6c275
  [NEW] +11.5Ki  [NEW] +11.3Ki    saluki_components::common::datadog::apm::ApmConfig::from_configuration::had70a6878fa7d173
  [NEW] +7.61Ki  [NEW] +7.48Ki    saluki_components::transforms::trace_sampler::score_sampler::ScoreSampler::sample::hfc28eb294ce41497
  [NEW] +6.13Ki  [NEW] +6.00Ki    _ZN76_<hickory_proto::rr::record_data::RData as core::clone::Clone>5clone17h61f3fe4fffa4b03dE.8776
  [NEW] +5.65Ki  [NEW] +5.50Ki    _<core::marker::PhantomData<T> as serde_core::de::DeserializeSeed>::deserialize::hf0643ecc9b96a441
  [NEW] +5.52Ki  [NEW] +5.39Ki    _ZN76_<hickory_proto::rr::record_data::RData as core::clone::Clone>5clone17h61f3fe4fffa4b03dE.11905
  [NEW] +5.35Ki  [NEW] +5.23Ki    _ZN59_<rustls::error::Error as core::clone::Clone>5clone17hd14a1219ce5dde1cE.10816
  [NEW] +5.27Ki  [NEW] +5.14Ki    _<saluki_core::data_model::event::trace::Span as core::clone::Clone>::clone::h67b60e9c023e938d
  [DEL] -5.21Ki  [DEL] -5.09Ki    _ZN59_<rustls::error::Error as core::clone::Clone>5clone17hd14a1219ce5dde1cE.11853
  [DEL] -5.35Ki  [DEL] -5.23Ki    _ZN59_<rustls::error::Error as core::clone::Clone>5clone17hd14a1219ce5dde1cE.10807
  [DEL] -5.52Ki  [DEL] -5.39Ki    _ZN76_<hickory_proto::rr::record_data::RData as core::clone::Clone>5clone17h61f3fe4fffa4b03dE.11890
  [DEL] -6.13Ki  [DEL] -6.00Ki    _ZN76_<hickory_proto::rr::record_data::RData as core::clone::Clone>5clone17h61f3fe4fffa4b03dE.8773
  [DEL] -10.5Ki  [DEL] -10.3Ki    _ZN76_<saluki_core::data_model::event::Event as core::clone::Clone>5clone17h7f500b934c4a671bE.10782
  [DEL] -11.1Ki  [DEL] -11.0Ki    saluki_components::common::datadog::apm::ApmConfig::from_configuration::hde97307d5b1f378a
  [DEL] -12.3Ki  [DEL] -12.1Ki    _<core::marker::PhantomData<T> as serde_core::de::DeserializeSeed>::deserialize::hf57b1009e3f2b7f6
  [DEL] -20.1Ki  [DEL] -20.0Ki    saluki_components::encoders::datadog::traces::TraceEndpointEncoder::encode_tracer_payload::h253c709930a63a8e
  [DEL] -27.3Ki  [DEL] -27.2Ki    saluki_components::transforms::apm_stats::ApmStats::process_trace::hf762265449fd0933
  +0.3% +89.6Ki  +0.3% +80.4Ki    TOTAL

pr-commenter · 2026-01-20T15:56:28Z

Regression Detector (Agent Data Plane)

Regression Detector Results

Run ID: 920e3daf-a7ba-4092-b53b-43d9a4826bd2

Baseline: be34af7
Comparison: b0ba6d8
Diff

❌ Experiments with retried target crashes

This is a critical error. One or more replicates failed with a non-zero exit code. These replicates may have been retried. See Replicate Execution Details for more information.

quality_gates_rss_dsd_low
quality_gates_rss_dsd_ultraheavy
otlp_ingest_traces_5mb_throughput

Optimization Goals: ❌ Regression(s) detected

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
❌	otlp_ingest_traces_5mb_cpu	% cpu utilization	+8.24	[+5.71, +10.78]	1	(metrics) (profiles) (logs)

Experiments ignored for regressions

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

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
❌	otlp_ingest_logs_5mb_memory	memory utilization	+9.24	[+8.75, +9.73]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_logs_5mb_throughput	ingress throughput	+0.01	[-0.12, +0.14]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_logs_5mb_cpu	% cpu utilization	-0.42	[-5.49, +4.65]	1	(metrics) (profiles) (logs)

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	dsd_uds_512kb_3k_contexts_cpu	% cpu utilization	+11.82	[-45.77, +69.41]	1	(metrics) (profiles) (logs)
❌	otlp_ingest_logs_5mb_memory	memory utilization	+9.24	[+8.75, +9.73]	1	(metrics) (profiles) (logs)
❌	otlp_ingest_traces_5mb_cpu	% cpu utilization	+8.24	[+5.71, +10.78]	1	(metrics) (profiles) (logs)
➖	dsd_uds_100mb_3k_contexts_cpu	% cpu utilization	+1.29	[-4.67, +7.25]	1	(metrics) (profiles) (logs)
➖	dsd_uds_10mb_3k_contexts_cpu	% cpu utilization	+0.96	[-29.25, +31.17]	1	(metrics) (profiles) (logs)
➖	dsd_uds_10mb_3k_contexts_memory	memory utilization	+0.36	[+0.16, +0.56]	1	(metrics) (profiles) (logs)
➖	dsd_uds_500mb_3k_contexts_memory	memory utilization	+0.36	[+0.17, +0.55]	1	(metrics) (profiles) (logs)
➖	dsd_uds_512kb_3k_contexts_memory	memory utilization	+0.33	[+0.15, +0.51]	1	(metrics) (profiles) (logs)
➖	quality_gates_rss_dsd_ultraheavy	memory utilization	+0.23	[+0.10, +0.37]	1	(metrics) (profiles) (logs)
➖	dsd_uds_500mb_3k_contexts_cpu	% cpu utilization	+0.21	[-1.07, +1.48]	1	(metrics) (profiles) (logs)
➖	dsd_uds_100mb_3k_contexts_memory	memory utilization	+0.19	[+0.00, +0.38]	1	(metrics) (profiles) (logs)
➖	dsd_uds_1mb_3k_contexts_memory	memory utilization	+0.18	[-0.01, +0.36]	1	(metrics) (profiles) (logs)
➖	quality_gates_rss_dsd_medium	memory utilization	+0.17	[-0.02, +0.37]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_traces_5mb_throughput	ingress throughput	+0.01	[-0.04, +0.06]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_logs_5mb_throughput	ingress throughput	+0.01	[-0.12, +0.14]	1	(metrics) (profiles) (logs)
➖	dsd_uds_512kb_3k_contexts_throughput	ingress throughput	+0.01	[-0.05, +0.06]	1	(metrics) (profiles) (logs)
➖	dsd_uds_1mb_3k_contexts_throughput	ingress throughput	+0.00	[-0.05, +0.06]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_metrics_5mb_throughput	ingress throughput	-0.00	[-0.13, +0.13]	1	(metrics) (profiles) (logs)
➖	dsd_uds_10mb_3k_contexts_throughput	ingress throughput	-0.01	[-0.14, +0.13]	1	(metrics) (profiles) (logs)
➖	dsd_uds_100mb_3k_contexts_throughput	ingress throughput	-0.01	[-0.06, +0.04]	1	(metrics) (profiles) (logs)
➖	quality_gates_rss_dsd_low	memory utilization	-0.07	[-0.23, +0.09]	1	(metrics) (profiles) (logs)
➖	quality_gates_rss_idle	memory utilization	-0.10	[-0.14, -0.05]	1	(metrics) (profiles) (logs)
➖	quality_gates_rss_dsd_heavy	memory utilization	-0.19	[-0.31, -0.06]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_logs_5mb_cpu	% cpu utilization	-0.42	[-5.49, +4.65]	1	(metrics) (profiles) (logs)
➖	dsd_uds_500mb_3k_contexts_throughput	ingress throughput	-0.49	[-0.62, -0.35]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_metrics_5mb_cpu	% cpu utilization	-0.70	[-6.72, +5.31]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_traces_5mb_memory	memory utilization	-1.31	[-2.01, -0.62]	1	(metrics) (profiles) (logs)
➖	otlp_ingest_metrics_5mb_memory	memory utilization	-3.50	[-3.73, -3.28]	1	(metrics) (profiles) (logs)
➖	dsd_uds_1mb_3k_contexts_cpu	% cpu utilization	-18.06	[-65.78, +29.65]	1	(metrics) (profiles) (logs)

Bounds Checks: ✅ Passed

perf	experiment	bounds_check_name	replicates_passed	links
✅	quality_gates_rss_dsd_heavy	memory_usage	10/10	(metrics) (profiles) (logs)
✅	quality_gates_rss_dsd_low	memory_usage	10/10	(metrics) (profiles) (logs)
✅	quality_gates_rss_dsd_medium	memory_usage	10/10	(metrics) (profiles) (logs)
✅	quality_gates_rss_dsd_ultraheavy	memory_usage	10/10	(metrics) (profiles) (logs)
✅	quality_gates_rss_idle	memory_usage	10/10	(metrics) (profiles) (logs)

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:

Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.
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.
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 Normal Replicate Execution Failures (non-profiling)

Experiment	Variant	Replicates	Failure	Debug Dashboard
otlp_ingest_traces_5mb_throughput	comparison	0	Failed to shutdown when requested	Debug Dashboard
quality_gates_rss_dsd_low	baseline	3	Failed to shutdown when requested	Debug Dashboard
quality_gates_rss_dsd_ultraheavy	baseline	3	Failed to shutdown when requested	Debug Dashboard

lib/saluki-components/src/encoders/datadog/traces/mod.rs

lib/saluki-components/src/transforms/trace_sampler/mod.rs

tobz · 2026-01-21T14:02:47Z

lib/saluki-components/src/transforms/trace_sampler/mod.rs

+}
+
+#[async_trait]
+impl Transform for TraceSampler {


Mostly saying this out loud so that I don't forget, but we'll likely want to end up making this a synchronous transform so that we can avoid the cost of message passing.

lib/saluki-components/src/transforms/trace_sampler/mod.rs

lib/saluki-core/src/data_model/event/trace/mod.rs

… metadata from the sampling transform component

lib/saluki-components/src/transforms/trace_sampler/mod.rs

…pling

andrewqian2001datadog · 2026-01-28T20:52:27Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-01-28T20:52:34Z

View all feedbacks in Devflow UI.

2026-01-28 20:52:34 UTC ℹ️ Start processing command /merge

2026-01-28 20:52:50 UTC ℹ️ MergeQueue: waiting for PR to be ready

This pull request is not mergeable according to GitHub. Common reasons include pending required checks, missing approvals, or merge conflicts — but it could also be blocked by other repository rules or settings.
It will be added to the queue as soon as checks pass and/or get approvals. View in MergeQueue UI.
Note: if you pushed new commits since the last approval, you may need additional approval.
You can remove it from the waiting list with /remove command.

2026-01-28 21:28:07 UTC ℹ️ MergeQueue: merge request added to the queue

The expected merge time in main is approximately 25m (p90).

2026-01-28 21:43:32 UTC 🚨 MergeQueue: This merge request is in error

mergequeue build completed successfully, but the github api returned an error while merging the pr.
It's probably because:

some status checks are failing:
- dd-gitlab/run-benchmarks-adp
target branch of PR is restricted to only allow up-to-date branches, but the pr is now outdated

Details

Error: PUT https://api.github.com/repos/DataDog/saluki/pulls/1110/merge: 405 Repository rule violations found

1 review requesting changes and 1 approving review by reviewers with write access.

14 of 14 required status checks are expected.

[] (Request ID: ED00:4E0E8:DC70FE:3D2421E:697A82FB)

FullStacktrace:
activity error (type: github.GithubService_MergePullRequest, scheduledEventID: 52, startedEventID: 53, identity: 1@github-worker-5b5f778c9d-h7jnk@): PUT https://api.github.com/repos/DataDog/saluki/pulls/1110/merge: 405 Repository rule violations found

1 review requesting changes and 1 approving review by reviewers with write access.

14 of 14 required status checks are expected.

[] (Request ID: ED00:4E0E8:DC70FE:3D2421E:697A82FB) (type: GitFailure, retryable: false): PUT https://api.github.com/repos/DataDog/saluki/pulls/1110/merge: 405 Repository rule violations found

1 review requesting changes and 1 approving review by reviewers with write access.

14 of 14 required status checks are expected.

[] (type: ErrorResponse, retryable: true)

andrewqian2001datadog · 2026-01-28T21:44:57Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-01-28T21:45:01Z

View all feedbacks in Devflow UI.

2026-01-28 21:45:01 UTC ℹ️ Start processing command /merge

2026-01-28 21:45:13 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in main is approximately 25m (p90).

2026-01-28 21:56:34 UTC 🚨 MergeQueue: This merge request is in error

mergequeue build completed successfully, but the github api returned an error while merging the pr.
It's probably because:

target branch of PR is restricted to only allow up-to-date branches, but the pr is now outdated

Details

Error: PUT https://api.github.com/repos/DataDog/saluki/pulls/1110/merge: 405 Repository rule violations found

1 review requesting changes and 1 approving review by reviewers with write access.

14 of 14 required status checks are expected.

[] (Request ID: ED00:4E0E8:EBF2D4:416EA64:697A860B)

FullStacktrace:
activity error (type: github.GithubService_MergePullRequest, scheduledEventID: 52, startedEventID: 53, identity: 1@github-worker-5b5f778c9d-h7jnk@): PUT https://api.github.com/repos/DataDog/saluki/pulls/1110/merge: 405 Repository rule violations found

1 review requesting changes and 1 approving review by reviewers with write access.

14 of 14 required status checks are expected.

[] (Request ID: ED00:4E0E8:EBF2D4:416EA64:697A860B) (type: GitFailure, retryable: false): PUT https://api.github.com/repos/DataDog/saluki/pulls/1110/merge: 405 Repository rule violations found

1 review requesting changes and 1 approving review by reviewers with write access.

14 of 14 required status checks are expected.

[] (type: ErrorResponse, retryable: true)

andrewqian2001datadog · 2026-01-28T21:57:06Z

/merge

gh-worker-devflow-routing-ef8351 · 2026-01-28T21:57:10Z

View all feedbacks in Devflow UI.

2026-01-28 21:57:10 UTC ℹ️ Start processing command /merge

2026-01-28 21:57:21 UTC ℹ️ MergeQueue: waiting for PR to be ready

This pull request is not mergeable according to GitHub. Common reasons include pending required checks, missing approvals, or merge conflicts — but it could also be blocked by other repository rules or settings.
It will be added to the queue as soon as checks pass and/or get approvals. View in MergeQueue UI.
Note: if you pushed new commits since the last approval, you may need additional approval.
You can remove it from the waiting list with /remove command.

2026-01-29 01:58:13 UTC ⚠️ MergeQueue: This merge request was unqueued

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

andrewqian2001datadog changed the title ~~Andrewq/add trace sampling~~ (WIP) Andrewq/add trace sampling Jan 20, 2026

github-actions bot added area/core Core functionality, event model, etc. area/components Sources, transforms, and destinations. labels Jan 20, 2026

tobz requested changes Jan 21, 2026

View reviewed changes

andrewqian2001datadog changed the title ~~(WIP) Andrewq/add trace sampling~~ [AGNTLOG-468] chore(datadog): add trace sampling Jan 21, 2026

andrewqian2001datadog added 11 commits January 21, 2026 10:36

modify the Trace event to include a TraceSampling field, which stores…

47f9942

… metadata from the sampling transform component

add the probabilistic sampler

704d1b1

add the error sampler

b3979ab

add the core sampler

55cdb76

add the score sampler

e921c3a

add setter for trace spans

b6dac83

add trace_sampler to mod.rs

de45c6d

checks for user set sampling in the translator

30b0625

add the trace sampler transform component

8017f4c

add helper class to compute signature

a32499f

modified the trace encoder to use sampling info from the transform

df45987

andrewqian2001datadog force-pushed the andrewq/add-trace-sampling branch from 942206a to df45987 Compare January 21, 2026 15:53

andrewqian2001datadog added 2 commits January 21, 2026 11:12

make check clippy + fmt

f5b45ed

wire up component

76ab423

andrewqian2001datadog marked this pull request as ready for review January 22, 2026 21:44

andrewqian2001datadog requested a review from a team as a code owner January 22, 2026 21:44

andrewqian2001datadog added 4 commits January 22, 2026 17:43

remove default macro which sets probablistic sampling to false

321b7f7

from tag from span which is already added to trace chunk

df98d8f

make fmt

740b8f7

remove tag added during translation process

ecdb386

rayz requested changes Jan 23, 2026

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lib/saluki-components/src/transforms/trace_sampler/mod.rs Show resolved Hide resolved

andrewqian2001datadog added 2 commits January 23, 2026 10:08

disable tag when probalistic sampler isn't being used

91254c7

revert change

43a889d

dd-devflow bot added the mergequeue-status: removed label Jan 28, 2026

Merge remote-tracking branch 'origin/main' into andrewq/add-trace-sam…

1186241

…pling

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dd-devflow bot added mergequeue-status: queued mergequeue-status: in_progress mergequeue-status: error and removed mergequeue-status: error mergequeue-status: queued mergequeue-status: in_progress labels Jan 28, 2026

Merge branch 'main' into andrewq/add-trace-sampling

b0ba6d8

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tobz merged commit e33b714 into main Jan 29, 2026
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tobz deleted the andrewq/add-trace-sampling branch January 29, 2026 13:57

dd-octo-sts bot pushed a commit that referenced this pull request Jan 29, 2026

[AGNTLOG-468] chore(datadog): add trace sampling (#1110) e33b714

84a6fee

[AGNTLOG-468] chore(datadog): add trace sampling #1110

[AGNTLOG-468] chore(datadog): add trace sampling #1110

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❌ Retried Normal Replicate Execution Failures (non-profiling)

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