discovery: improve e2e test output in case of failures

[Yumasi]

What does this PR do?

This PR makes the E2E test output for service discovery show more information about the running services, as well as being more precise as to what the actual issue is, and for which services.

Here are some examples:

Service not found

Before

Error:      	Expected value not to be nil.

After

	Error:      	Expected value not to be nil.
        	Test:       	TestLinuxTestSuite/TestServiceDiscoveryCheck
        	Messages:   	could not find service "rails_hello"
    host.go:131: 23-10-2024 16:32:46 - TestLinuxTestSuite/TestServiceDiscoveryCheck - Executing command `sudo systemctl status rails-svc`
    host.go:131: 23-10-2024 16:32:47 - TestLinuxTestSuite/TestServiceDiscoveryCheck - Executing command `sudo journalctl -u rails-svc`
    linux_test.go:130: Service "rails-svc" status:
        :● rails-svc.service - rails-svc
             Loaded: loaded (/etc/systemd/system/rails-svc.service; disabled; vendor preset: enabled)
             Active: active (running) since Wed 2024-10-23 14:31:34 UTC; 1min 12s ago
           Main PID: 27339 (ruby3.0)
              Tasks: 15 (limit: 4586)
             Memory: 66.0M
                CPU: 2.537s
             CGroup: /system.slice/rails-svc.service
                     └─27339 "puma 5.6.9 (tcp://localhost:7777) [rails-hello]"
        
        Oct 23 14:31:37 ip-10-1-59-25 rails[27339]: => Run `bin/rails server --help` for more startup options
        Oct 23 14:31:37 ip-10-1-59-25 rails[27339]: Puma starting in single mode...
        Oct 23 14:31:37 ip-10-1-59-25 rails[27339]: * Puma version: 5.6.9 (ruby 3.0.2-p107) ("Birdie's Version")

Field with unexpected value

Before

	Error:      	Not equal: 
        	           	expected: "python.intrumented"
        	           	actual  : "python.instrumented"
        	           	
        	           	Diff:
        	           	--- Expected
        	           	+++ Actual
        	           	@@ -1 +1 @@
        	           	-python.intrumented
        	           	+python.instrumented
        	Test:       	TestLinuxTestSuite/TestServiceDiscoveryCheck

After

	Error:      	Not equal: 
        	           	expected: "python.intrumented"
        	           	actual  : "python.instrumented"
        	           	
        	           	Diff:
        	           	--- Expected
        	           	+++ Actual
        	           	@@ -1 +1 @@
        	           	-python.intrumented
        	           	+python.instrumented
        	Test:       	TestLinuxTestSuite/TestServiceDiscoveryCheck
        	Messages:   	service "python.instrumented": service name

Motivation

USMON-1297

Describe how to test/QA your changes

Possible Drawbacks / Trade-offs

Additional Notes

[agent-platform-auto-pr[bot]]

Test changes on VM

Use this command from test-infra-definitions to manually test this PR changes on a VM:

inv create-vm --pipeline-id=47592551 --os-family=ubuntu

Note: This applies to commit 7eda563e

[agent-platform-auto-pr[bot]]

[Fast Unit Tests Report]

On pipeline 47592551 (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

[cit-pr-commenter[bot]]

Regression Detector

Regression Detector Results

Run ID: 7eb460be-6f00-4d64-8b87-f2653af17b3b Metrics dashboard Target profiles

Baseline: aac52bfde035df419009c2ad9a2833fbef6213b9 Comparison: 7eda563ebe86a7fe1e182f0de2847efa3a7b47af

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.

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	basic_py_check	% cpu utilization	+1.08	[-1.65, +3.82]	1	Logs
➖	quality_gate_idle_all_features	memory utilization	+0.98	[+0.87, +1.09]	1	Logs bounds checks dashboard
➖	file_to_blackhole_100ms_latency	egress throughput	+0.03	[-0.20, +0.25]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	+0.01	[-0.09, +0.11]	1	Logs
➖	file_to_blackhole_300ms_latency	egress throughput	+0.01	[-0.18, +0.19]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	+0.00	[-0.01, +0.01]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	-0.02	[-0.36, +0.32]	1	Logs
➖	quality_gate_idle	memory utilization	-0.03	[-0.08, +0.01]	1	Logs bounds checks dashboard
➖	file_to_blackhole_500ms_latency	egress throughput	-0.07	[-0.32, +0.18]	1	Logs
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	-0.16	[-0.89, +0.56]	1	Logs
➖	idle_all_features	memory utilization	-0.23	[-0.34, -0.12]	1	Logs bounds checks dashboard
➖	tcp_syslog_to_blackhole	ingress throughput	-0.25	[-0.30, -0.20]	1	Logs
➖	idle	memory utilization	-0.43	[-0.47, -0.38]	1	Logs bounds checks dashboard
➖	file_tree	memory utilization	-0.43	[-0.55, -0.30]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	-0.45	[-0.94, +0.03]	1	Logs
➖	otel_to_otel_logs	ingress throughput	-0.49	[-1.29, +0.32]	1	Logs
➖	pycheck_lots_of_tags	% cpu utilization	-2.71	[-5.23, -0.20]	1	Logs

Bounds Checks

perf	experiment	bounds_check_name	replicates_passed
✅	file_to_blackhole_0ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency	memory_usage	10/10
✅	file_to_blackhole_100ms_latency	memory_usage	10/10
✅	file_to_blackhole_300ms_latency	memory_usage	10/10
✅	file_to_blackhole_500ms_latency	memory_usage	10/10
✅	idle	memory_usage	10/10
✅	idle_all_features	memory_usage	10/10
✅	quality_gate_idle	memory_usage	10/10
✅	quality_gate_idle_all_features	memory_usage	10/10

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".

[Yumasi]

/merge

[dd-devflow[bot]]

:steam_locomotive: MergeQueue: pull request added to the queue

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Use /merge -c to cancel this operation!