[ebpfless] Add 5 second expiry to pending connections

[pimlu]

What does this PR do?

This PR adds a 5 second expiry to pending connections that didn't complete the handshake in time.

Motivation

Pending connections don't have a ConnectionStats object yet so the existing tracer logic won't expire them. Plus it's probably better to have a shorter timeout for pending connections (although the exact number we can decide, it will be a config later)

Describe how you validated your changes

Run the TCP processor test suite:

go test -tags=linux,linux_bpf,npm,process,test ./pkg/network/tracer/connection/ebpfless

In particular, the new test TestPendingConnExpiry should pass.

Possible Drawbacks / Trade-offs

This adds a timestamp into the connectionState structure which is effectively redundant with ConnectionStats. The reason to have it is, the ConnectionStats won't exist yet until the connection moves out of pending, so it has to be stored somewhere. But I think it would be good to refactor this in the future, will have to think about how to combine these responsibilities.

Additional Notes

[agent-platform-auto-pr]

Test changes on VM

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

inv aws.create-vm --pipeline-id=51285948 --os-family=ubuntu

Note: This applies to commit f348b29

[agent-platform-auto-pr]

Uncompressed package size comparison

Comparison with ancestor f215538d98687c4ca0d5620cd7750873446aeb2c

Diff per package

package	diff	status	size	ancestor	threshold
datadog-agent-amd64-deb	0.01MB	⚠️	1232.71MB	1232.71MB	140.00MB
datadog-agent-x86_64-rpm	0.01MB	⚠️	1241.95MB	1241.94MB	140.00MB
datadog-agent-x86_64-suse	0.01MB	⚠️	1241.95MB	1241.94MB	140.00MB
datadog-agent-arm64-deb	0.00MB	⚠️	968.50MB	968.50MB	140.00MB
datadog-agent-aarch64-rpm	0.00MB	⚠️	977.72MB	977.71MB	140.00MB
datadog-dogstatsd-amd64-deb	0.00MB	✅	78.53MB	78.53MB	10.00MB
datadog-dogstatsd-x86_64-rpm	0.00MB	✅	78.61MB	78.61MB	10.00MB
datadog-dogstatsd-x86_64-suse	0.00MB	✅	78.61MB	78.61MB	10.00MB
datadog-dogstatsd-arm64-deb	0.00MB	✅	55.75MB	55.75MB	10.00MB
datadog-heroku-agent-amd64-deb	0.00MB	✅	504.96MB	504.96MB	70.00MB
datadog-iot-agent-amd64-deb	0.00MB	✅	113.26MB	113.26MB	10.00MB
datadog-iot-agent-x86_64-rpm	0.00MB	✅	113.33MB	113.33MB	10.00MB
datadog-iot-agent-x86_64-suse	0.00MB	✅	113.33MB	113.33MB	10.00MB
datadog-iot-agent-arm64-deb	0.00MB	✅	108.72MB	108.72MB	10.00MB
datadog-iot-agent-aarch64-rpm	0.00MB	✅	108.79MB	108.79MB	10.00MB

Decision

⚠️ Warning

[cit-pr-commenter]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: f2214c1c-bd7f-45c5-9f1b-2b317b03acd5

Baseline: f215538
Comparison: f348b29
Diff

Optimization Goals: ✅ No significant changes detected

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	quality_gate_idle_all_features	memory utilization	+1.46	[+1.34, +1.59]	1	Logs bounds checks dashboard
➖	quality_gate_logs	% cpu utilization	+0.59	[-2.36, +3.54]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	+0.47	[-0.32, +1.27]	1	Logs
➖	tcp_syslog_to_blackhole	ingress throughput	+0.30	[+0.24, +0.35]	1	Logs
➖	otel_to_otel_logs	ingress throughput	+0.26	[-0.40, +0.92]	1	Logs
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	+0.26	[-0.46, +0.98]	1	Logs
➖	file_to_blackhole_500ms_latency	egress throughput	+0.18	[-0.59, +0.95]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	+0.07	[-0.80, +0.95]	1	Logs
➖	file_to_blackhole_1000ms_latency_linear_load	egress throughput	+0.05	[-0.41, +0.52]	1	Logs
➖	file_to_blackhole_0ms_latency_http2	egress throughput	+0.03	[-0.77, +0.82]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	+0.01	[-0.07, +0.09]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	+0.00	[-0.01, +0.01]	1	Logs
➖	file_to_blackhole_0ms_latency_http1	egress throughput	-0.01	[-0.81, +0.80]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	-0.01	[-0.72, +0.69]	1	Logs
➖	file_to_blackhole_300ms_latency	egress throughput	-0.01	[-0.64, +0.62]	1	Logs
➖	quality_gate_idle	memory utilization	-0.41	[-0.46, -0.37]	1	Logs bounds checks dashboard
➖	file_tree	memory utilization	-0.94	[-1.05, -0.83]	1	Logs

Bounds Checks: ❌ Failed

perf	experiment	bounds_check_name	replicates_passed	links
❌	file_to_blackhole_500ms_latency	lost_bytes	9/10
✅	file_to_blackhole_0ms_latency	lost_bytes	10/10
✅	file_to_blackhole_0ms_latency	memory_usage	10/10
✅	file_to_blackhole_0ms_latency_http1	lost_bytes	10/10
✅	file_to_blackhole_0ms_latency_http1	memory_usage	10/10
✅	file_to_blackhole_0ms_latency_http2	lost_bytes	10/10
✅	file_to_blackhole_0ms_latency_http2	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	memory_usage	10/10	bounds checks dashboard
✅	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

✅ Passed. All Quality Gates passed.

• 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, 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.

[pimlu]

/merge

[dd-devflow]

Devflow running: /merge

View all feedbacks in Devflow UI.

---

2024-12-17 01:46:22 UTC ℹ️ MergeQueue: waiting for PR to be ready

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.

---

2024-12-17 02:40:03 UTC ℹ️ MergeQueue: merge request added to the queue

The median merge time in main is 30m.

---

2024-12-17 03:05:09 UTC ℹ️ MergeQueue: This merge request was merged

[agent-platform-auto-pr]

[Fast Unit Tests Report]

On pipeline 51285948 (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