feat(shared-runtime): add block_on_with_timeout to BlockingRuntime by brettlangdon · Pull Request #2333 · DataDog/libdatadog

brettlangdon · 2026-08-07T13:00:43Z

What does this PR do?

Lets consumers bound a block_on wait with a deadline without adding tokio as a direct dependency — the executor is whatever the runtime already runs on.

Returns BlockOnTimeoutError::TimedOut/Io to distinguish a timeout from an executor failure.

Motivation

What inspired you to submit this pull request?

Additional Notes

Anything else we should know when reviewing?

How to test the change?

Describe here in detail how the change can be validated.

github-actions · 2026-08-07T13:02:25Z

📚 Documentation Check Results

⚠️ 213 documentation warning(s) found

📦 `libdd-shared-runtime` - 213 warning(s)

Updated: 2026-08-07 16:03:00 UTC | Commit: 5039b68 | missing-docs job results

github-actions · 2026-08-07T13:04:53Z

🔒 Cargo Deny Results

⚠️ 1 issue(s) found, showing only errors (advisories, bans, sources)

📦 `libdd-shared-runtime` - 1 error(s)

Show output

error[unsound]: Rand is unsound with a custom logger using `rand::rng()`
   ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:72:1
   │
72 │ rand 0.8.5 registry+https://github.com/rust-lang/crates.io-index
   │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unsound advisory detected
   │
   ├ ID: RUSTSEC-2026-0097
   ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0097
   ├ It has been reported (by [@lopopolo](https://github.com/lopopolo)) that the `rand` library is [unsound](https://rust-lang.github.io/unsafe-code-guidelines/glossary.html#soundness-of-code--of-a-library) (i.e. that safe code using the public API can cause Undefined Behaviour) when all the following conditions are met:
     
     - The `log` and `thread_rng` features are enabled
     - A [custom logger](https://docs.rs/log/latest/log/#implementing-a-logger) is defined
     - The custom logger accesses `rand::rng()` (previously `rand::thread_rng()`) and calls any `TryRng` (previously `RngCore`) methods on `ThreadRng`
     - The `ThreadRng` (attempts to) reseed while called from the custom logger (this happens every 64 kB of generated data)
     - Trace-level logging is enabled or warn-level logging is enabled and the random source (the `getrandom` crate) is unable to provide a new seed
     
     `TryRng` (previously `RngCore`) methods for `ThreadRng` use `unsafe` code to cast `*mut BlockRng<ReseedingCore>` to `&mut BlockRng<ReseedingCore>`. When all the above conditions are met this results in an aliased mutable reference, violating the Stacked Borrows rules. Miri is able to detect this violation in sample code. Since construction of [aliased mutable references is Undefined Behaviour](https://doc.rust-lang.org/stable/nomicon/references.html), the behaviour of optimized builds is hard to predict.
   ├ Announcement: https://github.com/rust-random/rand/pull/1763
   ├ Solution: Upgrade to >=0.10.1 OR <0.10.0, >=0.9.3 OR <0.9.0, >=0.8.6 (try `cargo update -p rand`)
   ├ rand v0.8.5
     └── (dev) libdd-common v5.1.0
         ├── libdd-capabilities-impl v3.0.0
         │   └── libdd-shared-runtime v2.0.0
         └── libdd-shared-runtime v2.0.0 (*)

advisories FAILED, bans ok, sources ok

Updated: 2026-08-07 16:04:30 UTC | Commit: 5039b68 | dependency-check job results

pr-commenter · 2026-08-07T13:13:40Z

Benchmarks

Comparison

Benchmark execution time: 2026-08-07 22:26:01

Comparing candidate commit 0f4a0ae in PR branch brettlangdon/block_on_timeout with baseline commit fbdace3 in branch main.

Found 2 performance improvements and 0 performance regressions! Performance is the same for 23 metrics, 0 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

🟩 = significantly better candidate vs. baseline
🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

scenario:trace_buffer/4_senders/no_delay

🟩 execution_time [-279.136µs; -243.058µs] or [-11.275%; -9.818%]
🟩 throughput [+162093.122op/s; +187705.075op/s] or [+11.140%; +12.901%]

Benchmark execution time: 2026-08-07 22:23:56

Comparing candidate commit 0f4a0ae in PR branch brettlangdon/block_on_timeout with baseline commit fbdace3 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 3 metrics, 0 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

🟩 = significantly better candidate vs. baseline
🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

Candidate

Candidate benchmark details

Group 1

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz	`0f4a0ae`	1786118305	brettlangdon/block_on_timeout

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
trace_buffer/1_senders/10us_delay	execution_time	56.344ms	56.647ms ± 0.151ms	56.643ms ± 0.103ms	56.743ms	56.913ms	57.055ms	57.148ms	0.89%	0.448	0.135	0.27%	0.011ms	1	200
trace_buffer/1_senders/10us_delay	throughput	15748.637op/s	15888.116op/s ± 42.293op/s	15889.016op/s ± 28.847op/s	15919.364op/s	15953.790op/s	15971.472op/s	15973.277op/s	0.53%	-0.433	0.109	0.27%	2.991op/s	1	200
trace_buffer/1_senders/1us_delay	execution_time	49.923ms	50.080ms ± 0.031ms	50.078ms ± 0.011ms	50.089ms	50.137ms	50.167ms	50.249ms	0.34%	0.670	7.065	0.06%	0.002ms	1	200
trace_buffer/1_senders/1us_delay	throughput	17910.917op/s	17971.147op/s ± 11.143op/s	17971.814op/s ± 4.055op/s	17976.036op/s	17987.133op/s	17990.661op/s	18027.643op/s	0.31%	-0.654	7.056	0.06%	0.788op/s	1	200
trace_buffer/1_senders/no_delay	execution_time	329.364µs	339.569µs ± 3.753µs	338.622µs ± 1.365µs	340.374µs	346.063µs	352.752µs	365.825µs	8.03%	2.844	13.891	1.10%	0.265µs	1	200
trace_buffer/1_senders/no_delay	throughput	2460195.474op/s	2650733.009op/s ± 28445.733op/s	2657831.271op/s ± 10749.832op/s	2666800.843op/s	2677817.837op/s	2682115.736op/s	2732537.586op/s	2.81%	-2.600	11.938	1.07%	2011.417op/s	1	200
trace_buffer/2_senders/10us_delay	execution_time	56.981ms	57.373ms ± 0.135ms	57.368ms ± 0.090ms	57.469ms	57.597ms	57.668ms	57.748ms	0.66%	-0.081	-0.032	0.23%	0.010ms	1	200
trace_buffer/2_senders/10us_delay	throughput	31170.084op/s	31373.627op/s ± 73.838op/s	31376.297op/s ± 48.969op/s	31419.834op/s	31490.965op/s	31551.210op/s	31589.738op/s	0.68%	0.095	-0.025	0.23%	5.221op/s	1	200
trace_buffer/2_senders/1us_delay	execution_time	50.025ms	50.122ms ± 0.042ms	50.112ms ± 0.021ms	50.139ms	50.202ms	50.232ms	50.278ms	0.33%	1.034	0.884	0.08%	0.003ms	1	200
trace_buffer/2_senders/1us_delay	throughput	35801.072op/s	35912.271op/s ± 30.060op/s	35919.656op/s ± 15.315op/s	35933.660op/s	35946.606op/s	35957.856op/s	35982.210op/s	0.17%	-1.030	0.873	0.08%	2.126op/s	1	200
trace_buffer/2_senders/no_delay	execution_time	840.347µs	892.704µs ± 19.309µs	891.587µs ± 13.452µs	906.990µs	924.580µs	929.355µs	936.870µs	5.08%	-0.053	-0.359	2.16%	1.365µs	1	200
trace_buffer/2_senders/no_delay	throughput	1921290.994op/s	2017286.462op/s ± 43734.282op/s	2018871.471op/s ± 30007.447op/s	2046711.406op/s	2083826.836op/s	2124794.918op/s	2141972.729op/s	6.10%	0.161	-0.259	2.16%	3092.481op/s	1	200
trace_buffer/4_senders/10us_delay	execution_time	57.341ms	57.601ms ± 0.116ms	57.576ms ± 0.060ms	57.651ms	57.818ms	57.997ms	58.016ms	0.76%	1.235	2.148	0.20%	0.008ms	1	200
trace_buffer/4_senders/10us_delay	throughput	62051.745op/s	62498.725op/s ± 125.847op/s	62526.411op/s ± 65.200op/s	62578.434op/s	62665.255op/s	62707.861op/s	62781.805op/s	0.41%	-1.219	2.103	0.20%	8.899op/s	1	200
trace_buffer/4_senders/1us_delay	execution_time	50.096ms	50.164ms ± 0.035ms	50.156ms ± 0.018ms	50.178ms	50.240ms	50.271ms	50.287ms	0.26%	1.125	1.267	0.07%	0.002ms	1	200
trace_buffer/4_senders/1us_delay	throughput	71589.534op/s	71765.173op/s ± 49.478op/s	71775.654op/s ± 25.726op/s	71797.940op/s	71826.606op/s	71842.410op/s	71862.064op/s	0.12%	-1.120	1.256	0.07%	3.499op/s	1	200
trace_buffer/4_senders/no_delay	execution_time	1.887ms	2.215ms ± 0.115ms	2.216ms ± 0.085ms	2.294ms	2.395ms	2.487ms	2.493ms	12.49%	0.019	-0.306	5.17%	0.008ms	1	200
trace_buffer/4_senders/no_delay	throughput	1444180.831op/s	1629894.844op/s ± 84933.850op/s	1624630.104op/s ± 61425.538op/s	1691004.313op/s	1776754.801op/s	1806561.631op/s	1907530.347op/s	17.41%	0.249	-0.160	5.20%	6005.730op/s	1	200
trace_buffer/8_senders/10us_delay	execution_time	57.628ms	57.923ms ± 0.228ms	57.828ms ± 0.103ms	58.079ms	58.416ms	58.556ms	58.615ms	1.36%	1.150	0.359	0.39%	0.016ms	1	200
trace_buffer/8_senders/10us_delay	throughput	122836.418op/s	124305.459op/s ± 486.894op/s	124506.670op/s ± 222.049op/s	124656.934op/s	124787.689op/s	124858.742op/s	124939.558op/s	0.35%	-1.138	0.323	0.39%	34.429op/s	1	200
trace_buffer/8_senders/1us_delay	execution_time	50.175ms	50.286ms ± 0.052ms	50.272ms ± 0.026ms	50.311ms	50.390ms	50.433ms	50.479ms	0.41%	1.114	1.175	0.10%	0.004ms	1	200
trace_buffer/8_senders/1us_delay	throughput	142634.144op/s	143181.679op/s ± 148.091op/s	143222.115op/s ± 73.155op/s	143276.032op/s	143346.141op/s	143445.825op/s	143498.061op/s	0.19%	-1.108	1.160	0.10%	10.472op/s	1	200
trace_buffer/8_senders/no_delay	execution_time	5.424ms	6.487ms ± 0.244ms	6.562ms ± 0.107ms	6.655ms	6.728ms	6.757ms	6.808ms	3.75%	-1.688	2.921	3.75%	0.017ms	1	200
trace_buffer/8_senders/no_delay	throughput	1057568.548op/s	1111652.503op/s ± 44803.886op/s	1097204.584op/s ± 17654.755op/s	1126591.075op/s	1222277.374op/s	1266843.421op/s	1327376.608op/s	20.98%	1.948	4.217	4.02%	3168.113op/s	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
trace_buffer/1_senders/10us_delay	execution_time	[56.626ms; 56.667ms] or [-0.037%; +0.037%]	None	None	None
trace_buffer/1_senders/10us_delay	throughput	[15882.254op/s; 15893.977op/s] or [-0.037%; +0.037%]	None	None	None
trace_buffer/1_senders/1us_delay	execution_time	[50.076ms; 50.085ms] or [-0.009%; +0.009%]	None	None	None
trace_buffer/1_senders/1us_delay	throughput	[17969.602op/s; 17972.691op/s] or [-0.009%; +0.009%]	None	None	None
trace_buffer/1_senders/no_delay	execution_time	[339.049µs; 340.089µs] or [-0.153%; +0.153%]	None	None	None
trace_buffer/1_senders/no_delay	throughput	[2646790.704op/s; 2654675.314op/s] or [-0.149%; +0.149%]	None	None	None
trace_buffer/2_senders/10us_delay	execution_time	[57.355ms; 57.392ms] or [-0.033%; +0.033%]	None	None	None
trace_buffer/2_senders/10us_delay	throughput	[31363.394op/s; 31383.860op/s] or [-0.033%; +0.033%]	None	None	None
trace_buffer/2_senders/1us_delay	execution_time	[50.116ms; 50.128ms] or [-0.012%; +0.012%]	None	None	None
trace_buffer/2_senders/1us_delay	throughput	[35908.105op/s; 35916.437op/s] or [-0.012%; +0.012%]	None	None	None
trace_buffer/2_senders/no_delay	execution_time	[890.028µs; 895.380µs] or [-0.300%; +0.300%]	None	None	None
trace_buffer/2_senders/no_delay	throughput	[2011225.311op/s; 2023347.613op/s] or [-0.300%; +0.300%]	None	None	None
trace_buffer/4_senders/10us_delay	execution_time	[57.585ms; 57.618ms] or [-0.028%; +0.028%]	None	None	None
trace_buffer/4_senders/10us_delay	throughput	[62481.283op/s; 62516.166op/s] or [-0.028%; +0.028%]	None	None	None
trace_buffer/4_senders/1us_delay	execution_time	[50.159ms; 50.168ms] or [-0.010%; +0.010%]	None	None	None
trace_buffer/4_senders/1us_delay	throughput	[71758.316op/s; 71772.031op/s] or [-0.010%; +0.010%]	None	None	None
trace_buffer/4_senders/no_delay	execution_time	[2.199ms; 2.231ms] or [-0.718%; +0.718%]	None	None	None
trace_buffer/4_senders/no_delay	throughput	[1618123.829op/s; 1641665.859op/s] or [-0.722%; +0.722%]	None	None	None
trace_buffer/8_senders/10us_delay	execution_time	[57.891ms; 57.954ms] or [-0.055%; +0.055%]	None	None	None
trace_buffer/8_senders/10us_delay	throughput	[124237.980op/s; 124372.938op/s] or [-0.054%; +0.054%]	None	None	None
trace_buffer/8_senders/1us_delay	execution_time	[50.279ms; 50.293ms] or [-0.014%; +0.014%]	None	None	None
trace_buffer/8_senders/1us_delay	throughput	[143161.155op/s; 143202.203op/s] or [-0.014%; +0.014%]	None	None	None
trace_buffer/8_senders/no_delay	execution_time	[6.453ms; 6.520ms] or [-0.521%; +0.521%]	None	None	None
trace_buffer/8_senders/no_delay	throughput	[1105443.116op/s; 1117861.891op/s] or [-0.559%; +0.559%]	None	None	None

Group 2

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz	`0f4a0ae`	1786118305	brettlangdon/block_on_timeout

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
concentrator/add_spans_to_concentrator	execution_time	9.546ms	9.572ms ± 0.016ms	9.568ms ± 0.010ms	9.582ms	9.605ms	9.618ms	9.634ms	0.69%	1.047	0.954	0.17%	0.001ms	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
concentrator/add_spans_to_concentrator	execution_time	[9.570ms; 9.575ms] or [-0.023%; +0.023%]	None	None	None

Group 1

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8175M CPU @ 2.50GHz	`0f4a0ae`	1786118305	brettlangdon/block_on_timeout

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
two way interface	execution_time	20.873µs	21.705µs ± 0.356µs	21.637µs ± 0.152µs	21.812µs	22.416µs	22.688µs	23.430µs	8.29%	1.553	4.203	1.64%	0.025µs	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
two way interface	execution_time	[21.656µs; 21.755µs] or [-0.227%; +0.227%]	None	None	None

Group 2

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8175M CPU @ 2.50GHz	`0f4a0ae`	1786118305	brettlangdon/block_on_timeout

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
write only interface	execution_time	2.059µs	2.076µs ± 0.008µs	2.075µs ± 0.003µs	2.079µs	2.095µs	2.101µs	2.106µs	1.51%	1.095	1.666	0.40%	0.001µs	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
write only interface	execution_time	[2.075µs; 2.077µs] or [-0.056%; +0.056%]	None	None	None

Group 3

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8175M CPU @ 2.50GHz	`0f4a0ae`	1786118305	brettlangdon/block_on_timeout

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
receiver_entry_point/report/2644	execution_time	5.234ms	5.352ms ± 0.101ms	5.286ms ± 0.031ms	5.464ms	5.499ms	5.516ms	5.522ms	4.46%	0.435	-1.660	1.88%	0.007ms	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
receiver_entry_point/report/2644	execution_time	[5.338ms; 5.366ms] or [-0.261%; +0.261%]	None	None	None

Baseline

Baseline benchmark details

Group 1

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz	`fbdace3`	1786121056	main

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
trace_buffer/1_senders/10us_delay	execution_time	56.349ms	56.614ms ± 0.154ms	56.589ms ± 0.085ms	56.678ms	56.870ms	57.189ms	57.223ms	1.12%	1.286	2.570	0.27%	0.011ms	1	200
trace_buffer/1_senders/10us_delay	throughput	15728.034op/s	15897.201op/s ± 42.978op/s	15904.015op/s ± 23.906op/s	15924.720op/s	15953.679op/s	15970.989op/s	15971.843op/s	0.43%	-1.263	2.481	0.27%	3.039op/s	1	200
trace_buffer/1_senders/1us_delay	execution_time	49.926ms	50.072ms ± 0.032ms	50.077ms ± 0.013ms	50.085ms	50.134ms	50.172ms	50.198ms	0.24%	0.199	3.368	0.06%	0.002ms	1	200
trace_buffer/1_senders/1us_delay	throughput	17929.102op/s	17974.175op/s ± 11.595op/s	17972.472op/s ± 4.708op/s	17981.050op/s	17989.796op/s	17992.047op/s	18026.521op/s	0.30%	-0.189	3.373	0.06%	0.820op/s	1	200
trace_buffer/1_senders/no_delay	execution_time	329.786µs	337.730µs ± 3.952µs	337.360µs ± 1.334µs	338.743µs	341.805µs	346.678µs	380.245µs	12.71%	6.363	65.564	1.17%	0.279µs	1	200
trace_buffer/1_senders/no_delay	throughput	2366894.230op/s	2665186.324op/s ± 29173.669op/s	2667775.634op/s ± 10522.355op/s	2677439.228op/s	2696282.635op/s	2715312.540op/s	2729045.865op/s	2.30%	-5.473	53.346	1.09%	2062.890op/s	1	200
trace_buffer/2_senders/10us_delay	execution_time	56.687ms	57.113ms ± 0.178ms	57.106ms ± 0.117ms	57.225ms	57.409ms	57.546ms	57.811ms	1.24%	0.268	0.606	0.31%	0.013ms	1	200
trace_buffer/2_senders/10us_delay	throughput	31135.964op/s	31516.740op/s ± 98.069op/s	31520.550op/s ± 64.470op/s	31580.572op/s	31675.155op/s	31730.663op/s	31753.362op/s	0.74%	-0.244	0.563	0.31%	6.935op/s	1	200
trace_buffer/2_senders/1us_delay	execution_time	50.027ms	50.113ms ± 0.037ms	50.107ms ± 0.021ms	50.129ms	50.192ms	50.219ms	50.253ms	0.29%	1.134	1.499	0.07%	0.003ms	1	200
trace_buffer/2_senders/1us_delay	throughput	35818.915op/s	35918.901op/s ± 26.165op/s	35923.482op/s ± 15.099op/s	35937.152op/s	35949.352op/s	35958.540op/s	35980.378op/s	0.16%	-1.130	1.486	0.07%	1.850op/s	1	200
trace_buffer/2_senders/no_delay	execution_time	852.351µs	901.288µs ± 19.266µs	901.535µs ± 12.700µs	913.431µs	931.191µs	944.852µs	980.572µs	8.77%	0.130	0.755	2.13%	1.362µs	1	200
trace_buffer/2_senders/no_delay	throughput	1835662.675op/s	1998049.523op/s ± 42669.434op/s	1996594.289op/s ± 27930.463op/s	2026781.788op/s	2065605.083op/s	2110016.028op/s	2111806.704op/s	5.77%	0.037	0.496	2.13%	3017.185op/s	1	200
trace_buffer/4_senders/10us_delay	execution_time	57.221ms	57.572ms ± 0.172ms	57.547ms ± 0.070ms	57.618ms	57.873ms	58.009ms	58.961ms	2.46%	3.113	20.572	0.30%	0.012ms	1	200
trace_buffer/4_senders/10us_delay	throughput	61057.490op/s	62530.907op/s ± 184.668op/s	62558.004op/s ± 76.026op/s	62632.013op/s	62748.242op/s	62802.809op/s	62913.820op/s	0.57%	-3.000	19.395	0.29%	13.058op/s	1	200
trace_buffer/4_senders/1us_delay	execution_time	50.112ms	50.171ms ± 0.037ms	50.162ms ± 0.017ms	50.181ms	50.254ms	50.294ms	50.334ms	0.34%	1.697	3.363	0.07%	0.003ms	1	200
trace_buffer/4_senders/1us_delay	throughput	71522.673op/s	71755.153op/s ± 53.355op/s	71767.007op/s ± 24.160op/s	71790.687op/s	71813.127op/s	71825.085op/s	71838.660op/s	0.10%	-1.691	3.340	0.07%	3.773op/s	1	200
trace_buffer/4_senders/no_delay	execution_time	2.328ms	2.476ms ± 0.061ms	2.480ms ± 0.046ms	2.523ms	2.567ms	2.586ms	2.590ms	4.42%	-0.247	-0.711	2.48%	0.004ms	1	200
trace_buffer/4_senders/no_delay	throughput	1390024.873op/s	1454995.745op/s ± 36390.954op/s	1451519.649op/s ± 26936.888op/s	1480755.382op/s	1518759.082op/s	1536313.453op/s	1546399.249op/s	6.54%	0.340	-0.634	2.49%	2573.229op/s	1	200
trace_buffer/8_senders/10us_delay	execution_time	57.587ms	57.887ms ± 0.226ms	57.813ms ± 0.121ms	58.008ms	58.383ms	58.483ms	58.805ms	1.72%	1.253	1.275	0.39%	0.016ms	1	200
trace_buffer/8_senders/10us_delay	throughput	122437.714op/s	124382.114op/s ± 483.842op/s	124538.394op/s ± 261.165op/s	124734.641op/s	124898.697op/s	124995.752op/s	125028.214op/s	0.39%	-1.233	1.198	0.39%	34.213op/s	1	200
trace_buffer/8_senders/1us_delay	execution_time	50.131ms	50.278ms ± 0.052ms	50.266ms ± 0.027ms	50.298ms	50.381ms	50.436ms	50.536ms	0.54%	1.461	3.576	0.10%	0.004ms	1	200
trace_buffer/8_senders/1us_delay	throughput	142472.549op/s	143204.264op/s ± 148.398op/s	143237.810op/s ± 76.234op/s	143299.504op/s	143364.341op/s	143399.866op/s	143624.230op/s	0.27%	-1.450	3.531	0.10%	10.493op/s	1	200
trace_buffer/8_senders/no_delay	execution_time	5.798ms	6.502ms ± 0.192ms	6.541ms ± 0.109ms	6.637ms	6.729ms	6.786ms	6.804ms	4.03%	-1.267	1.711	2.95%	0.014ms	1	200
trace_buffer/8_senders/no_delay	throughput	1058183.588op/s	1108416.007op/s ± 34136.177op/s	1100798.178op/s ± 18291.064op/s	1122234.135op/s	1169859.282op/s	1225818.230op/s	1241725.709op/s	12.80%	1.465	2.431	3.07%	2413.792op/s	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
trace_buffer/1_senders/10us_delay	execution_time	[56.593ms; 56.635ms] or [-0.038%; +0.038%]	None	None	None
trace_buffer/1_senders/10us_delay	throughput	[15891.245op/s; 15903.157op/s] or [-0.037%; +0.037%]	None	None	None
trace_buffer/1_senders/1us_delay	execution_time	[50.067ms; 50.076ms] or [-0.009%; +0.009%]	None	None	None
trace_buffer/1_senders/1us_delay	throughput	[17972.568op/s; 17975.782op/s] or [-0.009%; +0.009%]	None	None	None
trace_buffer/1_senders/no_delay	execution_time	[337.183µs; 338.278µs] or [-0.162%; +0.162%]	None	None	None
trace_buffer/1_senders/no_delay	throughput	[2661143.134op/s; 2669229.514op/s] or [-0.152%; +0.152%]	None	None	None
trace_buffer/2_senders/10us_delay	execution_time	[57.088ms; 57.138ms] or [-0.043%; +0.043%]	None	None	None
trace_buffer/2_senders/10us_delay	throughput	[31503.148op/s; 31530.331op/s] or [-0.043%; +0.043%]	None	None	None
trace_buffer/2_senders/1us_delay	execution_time	[50.108ms; 50.118ms] or [-0.010%; +0.010%]	None	None	None
trace_buffer/2_senders/1us_delay	throughput	[35915.275op/s; 35922.527op/s] or [-0.010%; +0.010%]	None	None	None
trace_buffer/2_senders/no_delay	execution_time	[898.618µs; 903.958µs] or [-0.296%; +0.296%]	None	None	None
trace_buffer/2_senders/no_delay	throughput	[1992135.950op/s; 2003963.097op/s] or [-0.296%; +0.296%]	None	None	None
trace_buffer/4_senders/10us_delay	execution_time	[57.548ms; 57.596ms] or [-0.041%; +0.041%]	None	None	None
trace_buffer/4_senders/10us_delay	throughput	[62505.314op/s; 62556.500op/s] or [-0.041%; +0.041%]	None	None	None
trace_buffer/4_senders/1us_delay	execution_time	[50.165ms; 50.176ms] or [-0.010%; +0.010%]	None	None	None
trace_buffer/4_senders/1us_delay	throughput	[71747.758op/s; 71762.547op/s] or [-0.010%; +0.010%]	None	None	None
trace_buffer/4_senders/no_delay	execution_time	[2.467ms; 2.484ms] or [-0.344%; +0.344%]	None	None	None
trace_buffer/4_senders/no_delay	throughput	[1449952.309op/s; 1460039.181op/s] or [-0.347%; +0.347%]	None	None	None
trace_buffer/8_senders/10us_delay	execution_time	[57.856ms; 57.918ms] or [-0.054%; +0.054%]	None	None	None
trace_buffer/8_senders/10us_delay	throughput	[124315.058op/s; 124449.170op/s] or [-0.054%; +0.054%]	None	None	None
trace_buffer/8_senders/1us_delay	execution_time	[50.271ms; 50.285ms] or [-0.014%; +0.014%]	None	None	None
trace_buffer/8_senders/1us_delay	throughput	[143183.698op/s; 143224.831op/s] or [-0.014%; +0.014%]	None	None	None
trace_buffer/8_senders/no_delay	execution_time	[6.475ms; 6.528ms] or [-0.410%; +0.410%]	None	None	None
trace_buffer/8_senders/no_delay	throughput	[1103685.062op/s; 1113146.953op/s] or [-0.427%; +0.427%]	None	None	None

Group 2

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz	`fbdace3`	1786121056	main

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
concentrator/add_spans_to_concentrator	execution_time	9.534ms	9.569ms ± 0.018ms	9.567ms ± 0.011ms	9.578ms	9.604ms	9.611ms	9.635ms	0.71%	0.634	0.374	0.19%	0.001ms	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
concentrator/add_spans_to_concentrator	execution_time	[9.566ms; 9.571ms] or [-0.026%; +0.026%]	None	None	None

Group 1

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8175M CPU @ 2.50GHz	`fbdace3`	1786121056	main

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
two way interface	execution_time	20.988µs	21.567µs ± 0.281µs	21.499µs ± 0.160µs	21.700µs	22.185µs	22.343µs	22.432µs	4.34%	0.960	0.641	1.30%	0.020µs	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
two way interface	execution_time	[21.528µs; 21.606µs] or [-0.181%; +0.181%]	None	None	None

Group 2

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8175M CPU @ 2.50GHz	`fbdace3`	1786121056	main

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
write only interface	execution_time	2.059µs	2.081µs ± 0.010µs	2.078µs ± 0.005µs	2.089µs	2.101µs	2.104µs	2.128µs	2.40%	0.995	1.285	0.49%	0.001µs	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
write only interface	execution_time	[2.080µs; 2.083µs] or [-0.068%; +0.068%]	None	None	None

Group 3

cpu_model	git_commit_sha	git_commit_date	git_branch
Intel(R) Xeon(R) Platinum 8175M CPU @ 2.50GHz	`fbdace3`	1786121056	main

scenario	metric	min	mean ± sd	median ± mad	p75	p95	p99	max	peak_to_median_ratio	skewness	kurtosis	cv	sem	runs	sample_size
receiver_entry_point/report/2644	execution_time	5.161ms	5.192ms ± 0.031ms	5.187ms ± 0.008ms	5.197ms	5.225ms	5.263ms	5.549ms	6.98%	7.828	84.532	0.60%	0.002ms	1	200

scenario	metric	95% CI mean	Shapiro-Wilk pvalue	Ljung-Box pvalue (lag=1)	Dip test pvalue
receiver_entry_point/report/2644	execution_time	[5.188ms; 5.196ms] or [-0.083%; +0.083%]	None	None	None

datadog-official · 2026-08-07T13:14:27Z

🎉 All green!

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 87.84%
• Overall Coverage: 75.90% (-0.01%)

_{This comment will be updated automatically if new data arrives.

🔗 Commit SHA: 0f4a0ae | Docs | Datadog PR Page | Give us feedback!}

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chatgpt-codex-connector · 2026-08-07T13:31:43Z

+        f: F,
+        timeout: std::time::Duration,
+    ) -> Result<F::Output, BlockOnTimeoutError> {
+        self.block_on(async move { tokio::time::timeout(timeout, f).await })?


Avoid panicking on timerless BlockingRuntime implementations

When this default is used by BasicRuntime::from_handle with a Tokio runtime built without enable_time/enable_all—a configuration that from_handle currently accepts—Tokio panics here with “timers are disabled” instead of returning BlockOnTimeoutError; the same applies to third-party BlockingRuntime implementations whose block_on is not Tokio-backed. This makes the new fallible API a potential process-aborting path when called through FFI, so missing timer support must be returned as an error or the timeout mechanism must be guaranteed by the trait.

AGENTS.md reference: AGENTS.md:L70-L76

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chatgpt-codex-connector · 2026-08-07T13:31:43Z

+    /// Drives `f` to completion, blocking the current thread, but gives up once `timeout`
+    /// elapses.
+    ///
+    /// A caller can bound a wait without adding tokio as a direct dependency. This method
+    /// drives the deadline on the same executor as [`block_on`](Self::block_on).


Do not promise a hard bound for non-yielding futures

When f performs blocking work or otherwise does not return Poll::Pending, Tokio cannot poll its timer until that work finishes, so this method can remain blocked well past timeout and then return Ok. The documentation's claims that it “gives up once timeout elapses” and lets callers “bound a wait” are therefore unsafe for the generic Future accepted here; either document that the deadline is cooperative and requires the future to yield, or execute the work in a way that can enforce the bound.

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dd-octo-sts · 2026-08-07T13:42:29Z

Artifact Size Benchmark Report

aarch64-alpine-linux-musl

Artifact	Baseline	Commit	Change
/aarch64-alpine-linux-musl/lib/libdatadog_profiling.a	89.19 MB	89.19 MB	+0% (+24 B) 👌
/aarch64-alpine-linux-musl/lib/libdatadog_profiling.so	8.20 MB	8.20 MB	0% (0 B) 👌

aarch64-unknown-linux-gnu

Artifact	Baseline	Commit	Change
/aarch64-unknown-linux-gnu/lib/libdatadog_profiling.so	11.06 MB	11.06 MB	0% (0 B) 👌
/aarch64-unknown-linux-gnu/lib/libdatadog_profiling.a	100.37 MB	100.37 MB	+0% (+16 B) 👌

libdatadog-x64-windows

Artifact	Baseline	Commit	Change
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.dll	26.63 MB	26.63 MB	0% (0 B) 👌
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.lib	94.56 KB	94.56 KB	0% (0 B) 👌
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.pdb	191.43 MB	191.44 MB	+0% (+8.00 KB) 👌
/libdatadog-x64-windows/debug/static/datadog_profiling_ffi.lib	1001.70 MB	1001.74 MB	+0% (+48.57 KB) 👌
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.dll	8.71 MB	8.71 MB	0% (0 B) 👌
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.lib	94.56 KB	94.56 KB	0% (0 B) 👌
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.pdb	25.62 MB	25.62 MB	0% (0 B) 👌
/libdatadog-x64-windows/release/static/datadog_profiling_ffi.lib	51.01 MB	51.01 MB	0% (0 B) 👌

libdatadog-x86-windows

Artifact	Baseline	Commit	Change
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.dll	23.22 MB	23.22 MB	0% (0 B) 👌
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.lib	96.04 KB	96.04 KB	0% (0 B) 👌
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.pdb	196.35 MB	196.36 MB	+0% (+8.00 KB) 👌
/libdatadog-x86-windows/debug/static/datadog_profiling_ffi.lib	990.83 MB	990.88 MB	+0% (+47.54 KB) 👌
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.dll	6.73 MB	6.73 MB	0% (0 B) 👌
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.lib	96.04 KB	96.04 KB	0% (0 B) 👌
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.pdb	27.55 MB	27.55 MB	--.02% (-8.00 KB) 💪
/libdatadog-x86-windows/release/static/datadog_profiling_ffi.lib	48.56 MB	48.56 MB	+0% (+2 B) 👌

x86_64-alpine-linux-musl

Artifact	Baseline	Commit	Change
/x86_64-alpine-linux-musl/lib/libdatadog_profiling.a	79.47 MB	79.47 MB	+0% (+16 B) 👌
/x86_64-alpine-linux-musl/lib/libdatadog_profiling.so	9.13 MB	9.13 MB	0% (0 B) 👌

x86_64-unknown-linux-gnu

Artifact	Baseline	Commit	Change
/x86_64-unknown-linux-gnu/lib/libdatadog_profiling.a	95.12 MB	95.12 MB	+0% (+16 B) 👌
/x86_64-unknown-linux-gnu/lib/libdatadog_profiling.so	11.14 MB	11.14 MB	0% (0 B) 👌

Lets consumers bound a block_on wait with a deadline without adding tokio as a direct dependency — the executor is whatever the runtime already runs on. Returns BlockOnTimeoutError::TimedOut/Io to distinguish a timeout from an executor failure.

brettlangdon marked this pull request as ready for review August 7, 2026 13:25

brettlangdon requested a review from a team as a code owner August 7, 2026 13:25

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brettlangdon force-pushed the brettlangdon/block_on_timeout branch from 067a252 to 0f4a0ae Compare August 7, 2026 15:58

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