Fix logs agent status output

[GustavoCaso]

What does this PR do?

We found an issue with the output of the logs agent status

CoreAgentProcessOpenFiles: %!f(uint64=27)
OSFileLimit: %!f(uint64=1048576)

The regression was introduced in this PR https://github.com/dataDog/datadog-agent/pull/22115

This PR adds a fix and provides unit test to reduce the likelihood of adding a similar regression in the future.

Motivation

Additional Notes

Possible Drawbacks / Trade-offs

Describe how to test/QA your changes

[pr-commenter[bot]]

Bloop Bleep... Dogbot Here

Regression Detector Results

Run ID: ee44938b-cb9f-4963-9282-6f475ba94037 Baseline: dd88f33e6653d5934786a3f00041d5f9f51a7f60 Comparison: edf56ceffed3657e699a86d65fcd06c59defba76 Total CPUs: 7

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

Experiments with missing or malformed data

• basic_py_check

Usually, this warning means that there is no usable optimization goal data for that experiment, which could be a result of misconfiguration.

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	-0.37	[-6.95, +6.21]

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI
➖	idle	memory utilization	+0.42	[+0.38, +0.46]
➖	file_tree	memory utilization	+0.41	[+0.32, +0.49]
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	+0.26	[-1.18, +1.69]
➖	trace_agent_msgpack	ingress throughput	+0.01	[+0.00, +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	-0.02	[-0.05, +0.02]
➖	process_agent_standard_check_with_stats	memory utilization	-0.28	[-0.31, -0.25]
➖	file_to_blackhole	% cpu utilization	-0.37	[-6.95, +6.21]
➖	process_agent_standard_check	memory utilization	-0.46	[-0.50, -0.42]
➖	tcp_syslog_to_blackhole	ingress throughput	-0.57	[-0.63, -0.51]
➖	process_agent_real_time_mode	memory utilization	-0.78	[-0.81, -0.74]
➖	otel_to_otel_logs	ingress throughput	-0.97	[-1.63, -0.30]

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".

[GustavoCaso]

/merge

[dd-devflow[bot]]

:steam_locomotive: MergeQueue

This merge request is not mergeable yet, because of pending checks/missing approvals. It will be added to the queue as soon as checks pass and/or get approvals. 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.

Use /merge -c to cancel this operation!

[dd-devflow[bot]]

:steam_locomotive: MergeQueue

Added to the queue.

There are 2 builds ahead of this PR! (estimated merge in less than 49m)

Use /merge -c to cancel this operation!