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[ASCII-1276] Fix host boot time off by one diff when called twice in test

Open pgimalac opened this issue 1 year ago • 1 comments

What does this PR do?

Ignore potential off-by-one difference in boot time value when calling gopsutil host.Info().

Motivation

The boot time can be computed dynamically from the uptime on some platforms, in which case the number of seconds can have an off by one difference depending on nanoseconds. Just allow this off by one to avoid the test being flaky.

Additional Notes

Possible Drawbacks / Trade-offs

Describe how to test/QA your changes

pgimalac avatar Mar 11 '24 15:03 pgimalac

Bloop Bleep... Dogbot Here

Regression Detector Results

Run ID: a3e90514-14d3-454e-ae72-24a6faf1aa2b Baseline: 26cd8c729cc1e8203f5cdd4d1d95287f4cdac3ea Comparison: 08caf3d8cba39de298c714fff66b89aa2e526147

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

No significant changes in experiment optimization goals

Confidence level: 90.00% Effect size tolerance: |Δ mean %| ≥ 5.00%

There were no significant changes in experiment optimization goals at this confidence level and effect size tolerance.

Experiments ignored for regressions

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

perf experiment goal Δ mean % Δ mean % CI
file_to_blackhole % cpu utilization -0.89 [-7.42, +5.63]

Fine details of change detection per experiment

perf experiment goal Δ mean % Δ mean % CI
uds_dogstatsd_to_api_cpu % cpu utilization +2.19 [+0.74, +3.64]
file_tree memory utilization +0.63 [+0.55, +0.70]
process_agent_standard_check memory utilization +0.56 [+0.52, +0.60]
tcp_syslog_to_blackhole ingress throughput +0.42 [+0.37, +0.47]
process_agent_standard_check_with_stats memory utilization +0.33 [+0.29, +0.38]
otel_to_otel_logs ingress throughput +0.24 [-0.38, +0.86]
trace_agent_msgpack ingress throughput +0.01 [+0.01, +0.02]
uds_dogstatsd_to_api ingress throughput +0.00 [-0.00, +0.00]
tcp_dd_logs_filter_exclude ingress throughput +0.00 [-0.00, +0.00]
trace_agent_json ingress throughput -0.01 [-0.04, +0.03]
idle memory utilization -0.87 [-0.91, -0.82]
file_to_blackhole % cpu utilization -0.89 [-7.42, +5.63]
process_agent_real_time_mode memory utilization -1.48 [-1.52, -1.43]
basic_py_check % cpu utilization -3.34 [-5.65, -1.04]

Explanation

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:

  1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

  2. 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.

  3. Its configuration does not mark it "erratic".

pr-commenter[bot] avatar Mar 11 '24 16:03 pr-commenter[bot]

/merge

pgimalac avatar Mar 12 '24 15:03 pgimalac

:steam_locomotive: MergeQueue

Pull request added to the queue.

This build is going to start soon! (estimated merge in less than 27m)

Use /merge -c to cancel this operation!

dd-devflow[bot] avatar Mar 12 '24 15:03 dd-devflow[bot]