enhancement(antithesis): floor buffer size, multi-value packed metrics

[blt]

Summary

Expand the antithesis rig to:

• ship multi-value metric lines to ADP
• ensure that dogstatsd_buffer_size is mostly larger than 128 bytes without excluding smaller values and
• tidy up an assertion name to reflect actual semantics around sends.

Change Type

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

How did you test this PR?

Run under antithesis.

References

N/A

[blt]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• enhancement(antithesis): floor buffer size, multi-value packed metrics #1799 : 2 dependent PRs (#1800 , #1826 ) 👈 (View in Graphite)
• enhancement(antithesis): Expand SDK assertions, hammer sketch #1785
• enhancement(antithesis): DogStatsD load generation #1782
• enhancement(antithesis): Vary datadog.yaml in test/antithesis, assert aliveness #1779
• docs(antithesis): Antithesis research scratchbook and bug ledger #1768 : 2 other dependent PRs (#1769 , #1787 )
• chore(antithesis): Antithesis test harness and workload #1767
• enhancement(correctness): Create test/antithesis sub-project  #1774
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[datadog-datadog-prod-us1]

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[pr-commenter]

Binary Size Analysis (Agent Data Plane)

Baseline: d93575e · Comparison: 5e18a53 · diff
Analysis Configuration: stripped binaries · Pass/Fail Threshold: +5%
Sizes: 38.10 MiB (baseline) vs 38.00 MiB (comparison)
Size Change: -106.66 KiB (-0.27%)

✅ Binary size difference within threshold

Changes by Module

Module	File Size	Symbols
core	+30.83 KiB	1936
prost	-30.63 KiB	98
figment	-29.26 KiB	220
tokio	-12.38 KiB	656
tonic	-9.36 KiB	184
h2	+8.46 KiB	83
hyper	-7.61 KiB	165
alloc	+7.37 KiB	704
anyhow	-6.00 KiB	358
agent_data_plane::cli::run	-5.93 KiB	10
[sections]	-5.52 KiB	7
rustls	-4.49 KiB	185
http_body_util	-4.33 KiB	37
[Unmapped]	+4.32 KiB	1
anon.b1989804c321c6229c83a9d121c3ffb0.48.llvm.15956482214170139656	+4.00 KiB	1
anon.ae75cd3060d8b952a6fd466cba97c1c5.103.llvm.298110800033293764	-3.91 KiB	1
agent_data_plane::components::ottl_transform_processor	-3.67 KiB	9
serde_yaml	-3.61 KiB	44
tower	-3.60 KiB	113
serde_core	-3.23 KiB	82

Detailed Symbol Changes

    FILE SIZE        VM SIZE    
 --------------  -------------- 
  [NEW] +5.59Ki  [NEW]    +359    core::ptr::drop_in_place<http_body_util::combinators::map_err::MapErr<http_body_util::combinators::map_err::MapErr<http_body_util::combinators::map_frame::MapFrame<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::remoteagent::v1::RefreshRemoteAgentResponse>::new<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::remoteagent::v1::RefreshRemoteAgentResponse>>::{{closure}}>,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::remoteagent::v1::RefreshRemoteAgentResponse>::new<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::remoteagent::v1::RefreshRemoteAgentResponse>>::{{closure}}>,tonic::status::Status::map_error<tonic::status::S
  [NEW] +5.44Ki  [NEW] +5.29Ki    _<figment::value::magic::RelativePathBuf as figment::value::magic::Magic>::deserialize_from::hcfd625ee9333661b
  [NEW] +5.19Ki  [NEW] +4.89Ki    alloc::collections::btree::node::Handle<alloc::collections::btree::node::NodeRef<alloc::collections::btree::node::marker::Mut,K,V,alloc::collections::btree::node::marker::Leaf>,alloc::collections::btree::node::marker::Edge>::insert_recursing::h5a7d8ef71dfe1d76
  [NEW] +5.02Ki  [NEW]    +359    core::ptr::drop_in_place<http_body_util::combinators::map_err::MapErr<http_body_util::combinators::map_frame::MapFrame<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::model::v1::HostTagReply>::new<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::model::v1::HostTagReply>>::{{closure}}>,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::model::v1::HostTagReply>::new<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::model::v1::HostTagReply>>::{{closure}}>>::hb8a4232a81af1918
  [NEW] +5.00Ki  [NEW] +4.70Ki    alloc::collections::btree::node::Handle<alloc::collections::btree::node::NodeRef<alloc::collections::btree::node::marker::Mut,K,V,alloc::collections::btree::node::marker::Leaf>,alloc::collections::btree::node::marker::Edge>::insert_recursing::h0fe2dbb6a6a94df1
  [NEW] +4.99Ki  [NEW] +4.84Ki    _<figment::value::magic::Tagged<T> as figment::value::magic::Magic>::deserialize_from::he774f97a97ff55b1
  +9.2% +4.92Ki  +9.3% +4.92Ki    saluki_core::topology::blueprint::TopologyBlueprint::build::_{{closure}}::hbf871b3913e42c66
  [NEW] +4.83Ki  [NEW] +4.58Ki    agent_data_plane::components::ottl_filter_processor::config::_::_<impl serde_core::de::Deserialize for agent_data_plane::components::ottl_filter_processor::config::OttlFilterConfig>::deserialize::h4f4429612e2653e9
  [NEW] +4.77Ki  [NEW] +4.47Ki    alloc::collections::btree::node::Handle<alloc::collections::btree::node::NodeRef<alloc::collections::btree::node::marker::Mut,K,V,alloc::collections::btree::node::marker::Leaf>,alloc::collections::btree::node::marker::Edge>::insert_recursing::h859019f427a7299f
  [NEW] +4.74Ki  [NEW] +4.58Ki    _<figment::value::de::ConfiguredValueDe<I> as serde_core::de::Deserializer>::deserialize_struct::ha66bb36cad767a6d
  [NEW] +4.52Ki  [NEW] +4.22Ki    alloc::collections::btree::node::Handle<alloc::collections::btree::node::NodeRef<alloc::collections::btree::node::marker::Mut,K,V,alloc::collections::btree::node::marker::Leaf>,alloc::collections::btree::node::marker::Edge>::insert_recursing::hea023ce38d3adc08
  [DEL] -4.78Ki  [DEL] -4.62Ki    _<figment::value::de::ConfiguredValueDe<I> as serde_core::de::Deserializer>::deserialize_struct::h7a39627207e3f3a4
  [DEL] -4.80Ki  [DEL] -4.64Ki    _<figment::value::magic::RelativePathBuf as figment::value::magic::Magic>::deserialize_from::h6ff9f06009392c01
  [DEL] -4.85Ki  [DEL] -4.59Ki    agent_data_plane::components::ottl_transform_processor::config::_::_<impl serde_core::de::Deserialize for agent_data_plane::components::ottl_transform_processor::config::OttlTransformConfig>::deserialize::hc55bc685ff741938
  [DEL] -5.12Ki  [DEL] -5.01Ki    alloc::collections::btree::map::BTreeMap<K,V,A>::insert::hba0bacef74150a71
  -0.5% -5.12Ki  -0.5% -5.12Ki    [section .gcc_except_table]
  [DEL] -5.30Ki  [DEL]     -51    core::ptr::drop_in_place<http_body_util::combinators::map_err::MapErr<http_body_util::combinators::map_err::MapErr<http_body_util::combinators::map_frame::MapFrame<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::model::v1::HostTagReply>::new<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::model::v1::HostTagReply>>::{{closure}}>,tonic::codec::decode::Streaming<datadog_protos::agent_include::datadog::model::v1::HostTagReply>::new<tonic::service::interceptor::ResponseBody<tonic::body::Body>,tonic_prost::codec::ProstDecoder<datadog_protos::agent_include::datadog::model::v1::HostTagReply>>::{{closure}}>,tonic::status::Status::map_error<tonic::status::Status>>>::h7c1e60183b87d306
  [DEL] -5.38Ki  [DEL] -5.23Ki    _<figment::value::magic::Tagged<T> as figment::value::magic::Magic>::deserialize_from::h4482918f844c4c1b
  [DEL] -5.73Ki  [DEL] -5.58Ki    _<figment::value::magic::RelativePathBuf as figment::value::magic::Magic>::deserialize_from::hd72d65f5176e7f06
  -4.1% -6.16Ki  -4.1% -6.16Ki    agent_data_plane::cli::run::handle_run_command::_{{closure}}::h0215ea3520b410a0
  -0.9%  -114Ki  -1.3%  -130Ki    [12905 Others]
  -0.3%  -106Ki  -0.4%  -128Ki    TOTAL

[pr-commenter]

Regression Detector (Agent Data Plane)

Run ID: 6cc0a0fe-21b5-4632-acf5-2e50b0fa922d
Baseline: d93575ee · Comparison: 5e18a532 · 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_100mb_3k_contexts_cpu (erratic)	cpu	⚪ +4.08	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_cpu (erratic)	cpu	⚪ +4.04	metrics profiles logs
dsd_uds_512kb_3k_contexts_cpu (erratic)	cpu	⚪ +3.80	metrics profiles logs
otlp_ingest_metrics_5mb_cpu (erratic)	cpu	⚪ +3.09	metrics profiles logs
otlp_ingest_traces_5mb_cpu (erratic)	cpu	⚪ +1.33	metrics profiles logs
otlp_ingest_logs_5mb_cpu (ignored)	cpu	⚪ +0.55	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_throughput	throughput	⚪ -0.27	metrics profiles logs
otlp_ingest_traces_5mb_throughput	throughput	⚪ -0.20	metrics profiles logs
quality_gates_rss_dsd_ultraheavy	memory	⚪ +0.19	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_cpu (erratic)	cpu	⚪ +0.11	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_throughput	throughput	⚪ -0.03	metrics profiles logs
dsd_uds_10mb_3k_contexts_throughput	throughput	⚪ -0.01	metrics profiles logs
otlp_ingest_logs_5mb_throughput (ignored)	throughput	⚪ -0.01	metrics profiles logs
dsd_uds_512kb_3k_contexts_throughput	throughput	⚪ -0.00	metrics profiles logs
dsd_uds_1mb_3k_contexts_throughput	throughput	⚪ +0.00	metrics profiles logs
dsd_uds_100mb_3k_contexts_throughput	throughput	⚪ +0.01	metrics profiles logs
otlp_ingest_metrics_5mb_throughput	throughput	⚪ +0.01	metrics profiles logs
otlp_ingest_traces_ottl_filtering_5mb_memory	memory	⚪ -0.17	metrics profiles logs
quality_gates_rss_dsd_medium	memory	⚪ -0.20	metrics profiles logs
otlp_ingest_traces_ottl_transform_5mb_memory	memory	⚪ -0.25	metrics profiles logs
otlp_ingest_traces_5mb_memory	memory	⚪ -0.26	metrics profiles logs
dsd_uds_500mb_3k_contexts_cpu (erratic)	cpu	⚪ -0.47	metrics profiles logs
quality_gates_rss_dsd_heavy	memory	⚪ -0.49	metrics profiles logs
otlp_ingest_metrics_5mb_memory	memory	⚪ -0.60	metrics profiles logs
dsd_uds_10mb_3k_contexts_memory	memory	⚪ -0.65	metrics profiles logs
dsd_uds_500mb_3k_contexts_memory	memory	⚪ -0.68	metrics profiles logs
quality_gates_rss_idle	memory	⚪ -0.71	metrics profiles logs
dsd_uds_100mb_3k_contexts_memory	memory	⚪ -0.80	metrics profiles logs
quality_gates_rss_dsd_low	memory	⚪ -0.84	metrics profiles logs
dsd_uds_1mb_3k_contexts_memory	memory	⚪ -0.87	metrics profiles logs
dsd_uds_512kb_3k_contexts_memory	memory	⚪ -0.95	metrics profiles logs
dsd_uds_500mb_3k_contexts_throughput	throughput	⚪ +1.11	metrics profiles logs
dsd_uds_1mb_3k_contexts_cpu (erratic)	cpu	⚪ -3.71	metrics profiles logs
dsd_uds_10mb_3k_contexts_cpu (erratic)	cpu	🟢 -5.42	metrics profiles logs
otlp_ingest_logs_5mb_memory (ignored)	memory	⚪ -10.19	metrics profiles logs

Bounds Checks: ✅ Passed (5)

experiment	check	replicates	observed	links
quality_gates_rss_dsd_heavy	memory_usage	10/10	✅ 115 MiB ≤ 140 MiB	metrics profiles logs
quality_gates_rss_dsd_low	memory_usage	10/10	✅ 39.6 MiB ≤ 50 MiB	metrics profiles logs
quality_gates_rss_dsd_medium	memory_usage	10/10	✅ 60.2 MiB ≤ 75 MiB	metrics profiles logs
quality_gates_rss_dsd_ultraheavy	memory_usage	10/10	✅ 184 MiB ≤ 200 MiB	metrics profiles logs
quality_gates_rss_idle	memory_usage	10/10	✅ 26.8 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

Expands the Antithesis DogStatsD workload generator to occasionally emit multi-value (:-packed) metric values, adds a “multi-value emitted” assertion anchor to keep that behavior non-vacuous under Antithesis, and adjusts sampled DogStatsD receive-buffer sizing so most runs use realistic (>=128B) buffers while still probing edge/boundary values.

Changes:

• Add multi-value packed metric value generation and plumb a boolean signal up through dogstatsd::send for assertions.
• Add an Antithesis assertion anchor that a workload sometimes emits a multi-value metric.
• Bias dogstatsd_buffer_size sampling toward >=128B values while keeping rare small/boundary probes.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
test/antithesis/scratchbook/existing-assertions.md	Updates assertion inventory text/table to reflect the new multi-value anchor (but contains an inaccurate ripgrep claim).
test/antithesis/harness/src/payload/dogstatsd/metrics.rs	Emits multi-value :-packed metric values (~5%) and returns whether packing occurred.
test/antithesis/harness/src/payload/dogstatsd.rs	Propagates “multi-value emitted” signal from metric writer through send().
test/antithesis/harness/src/bin/parallel_driver_send_dogstatsd.rs	Tracks whether any multi-value metric was generated and asserts it happens sometimes.
test/antithesis/harness/src/bin/first_sample_config/config.rs	Introduces sample_buffer_size to keep most buffer sizes >=128B while preserving rare boundary probes.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.