Introduce a quality gate experiment for "usual" logs tailing

[blt]

What does this PR do?

This commit introduces a quality gates experiments meant to demonstrate that logs Agent will not lose logs and will not consume too much memory when operating in a "usual" logs tailing situation. Logs are produced in two sources at 500 KiB/second and rotate 5 total times at 50 MiB. Intake latency is 75ms.

Motivation

Protect the 'usual' logs tailing scenario from performance regression.

Additional Notes

Exact details may change once we haggle some with AML.

[cit-pr-commenter]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: 83430be3-c3dd-4343-b8c4-c5d1e4f47f56

Baseline: a166214
Comparison: 5613511
Diff

Optimization Goals: ✅ No significant changes detected

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	pycheck_lots_of_tags	% cpu utilization	+2.81	[-0.74, +6.36]	1	Logs
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	+2.04	[+1.31, +2.78]	1	Logs
➖	quality_gate_logs	% cpu utilization	+1.40	[-1.50, +4.31]	1	Logs
➖	otel_to_otel_logs	ingress throughput	+0.63	[-0.02, +1.27]	1	Logs
➖	quality_gate_idle	memory utilization	+0.16	[+0.10, +0.22]	1	Logs bounds checks dashboard
➖	file_to_blackhole_500ms_latency	egress throughput	+0.10	[-0.67, +0.87]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	+0.01	[-0.08, +0.11]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	+0.01	[-0.80, +0.82]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	-0.00	[-0.01, +0.01]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	-0.00	[-0.77, +0.77]	1	Logs
➖	file_to_blackhole_1000ms_latency_linear_load	egress throughput	-0.00	[-0.47, +0.46]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	-0.01	[-0.71, +0.70]	1	Logs
➖	file_to_blackhole_300ms_latency	egress throughput	-0.02	[-0.64, +0.60]	1	Logs
➖	basic_py_check	% cpu utilization	-0.09	[-3.99, +3.81]	1	Logs
➖	tcp_syslog_to_blackhole	ingress throughput	-0.36	[-0.42, -0.30]	1	Logs
➖	file_tree	memory utilization	-0.67	[-0.82, -0.52]	1	Logs
➖	quality_gate_idle_all_features	memory utilization	-1.32	[-1.46, -1.17]	1	Logs bounds checks dashboard

Bounds Checks: ❌ Failed

perf	experiment	bounds_check_name	replicates_passed	links
❌	file_to_blackhole_1000ms_latency	lost_bytes	0/10
❌	file_to_blackhole_0ms_latency	lost_bytes	9/10
❌	file_to_blackhole_500ms_latency	lost_bytes	9/10
❌	quality_gate_idle	memory_usage	9/10	bounds checks dashboard
✅	file_to_blackhole_0ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency_linear_load	memory_usage	10/10
✅	file_to_blackhole_100ms_latency	lost_bytes	10/10
✅	file_to_blackhole_100ms_latency	memory_usage	10/10
✅	file_to_blackhole_300ms_latency	lost_bytes	10/10
✅	file_to_blackhole_300ms_latency	memory_usage	10/10
✅	file_to_blackhole_500ms_latency	memory_usage	10/10
✅	quality_gate_idle_all_features	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_logs	lost_bytes	10/10
✅	quality_gate_logs	memory_usage	10/10

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:

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".

CI Pass/Fail Decision

❌ Failed. Some Quality Gates were violated.

• quality_gate_idle_all_features, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_idle, bounds check memory_usage: 9/10 replicas passed. Failed 1 which is > 0. Gate FAILED.
• quality_gate_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check lost_bytes: 10/10 replicas passed. Gate passed.

[agent-platform-auto-pr]

[Fast Unit Tests Report]

On pipeline 49690912 (CI Visibility). The following jobs did not run any unit tests:

Jobs:

• tests_deb-arm64-py3
• tests_deb-x64-py3
• tests_flavor_dogstatsd_deb-x64
• tests_flavor_heroku_deb-x64
• tests_flavor_iot_deb-x64
• tests_rpm-arm64-py3
• tests_rpm-x64-py3
• tests_windows-x64

If you modified Go files and expected unit tests to run in these jobs, please double check the job logs. If you think tests should have been executed reach out to #agent-devx-help

[goxberry]

I think if this experiment's name starts with quality_gate, it may become mandatory in Agent CI -- we might want to check that before merge.

[goxberry]

quality_gate_idle, bounds check memory_usage: 9/10 replicas passed. Failed 1 which is > 0. Gate FAILED.
quality_gate_logs, bounds check lost_bytes: 10/10 replicas passed. Gate passed.
quality_gate_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
quality_gate_idle_all_features, bounds check memory_usage: 10/10 replicas passed. Gate passed.

^ Confirms that the new experiments will become mandatory.

[blt]

/merge

[dd-devflow]

Devflow running: /merge

View all feedbacks in Devflow UI.

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2024-11-28 00:53:15 UTC ℹ️ MergeQueue: pull request added to the queue

The median merge time in main is 22m.