[CWS] Remove container_id from kernel context

[lebauce]

What does this PR do?

Do not store the container_id kernel side.

Motivation

Now that we have a way to identify a cgroup (using its path key), we do not need
to store the container id kernel side, saving 64 bytes per proc_cache entry which
can amount to 8 MB on some hosts.

Describe how you validated your changes

Possible Drawbacks / Trade-offs

Additional Notes

[agent-platform-auto-pr]

Uncompressed package size comparison

Comparison with ancestor c0121d28c8366b18fcd2ee81d04535623cdce7a8

Size reduction summary

package	diff	status	size	ancestor	threshold
datadog-agent-x86_64-rpm	-0.21MB	✅	824.77MB	824.98MB	0.50MB
datadog-agent-x86_64-suse	-0.21MB	✅	824.77MB	824.98MB	0.50MB
datadog-agent-amd64-deb	-0.21MB	✅	814.98MB	815.19MB	0.50MB
datadog-agent-arm64-deb	-0.22MB	✅	805.85MB	806.06MB	0.50MB
datadog-agent-aarch64-rpm	-0.22MB	✅	815.62MB	815.84MB	0.50MB

Diff per package

package	diff	status	size	ancestor	threshold
datadog-dogstatsd-amd64-deb	0.00MB	✅	39.46MB	39.46MB	0.50MB
datadog-dogstatsd-x86_64-rpm	0.00MB	✅	39.54MB	39.54MB	0.50MB
datadog-dogstatsd-x86_64-suse	0.00MB	✅	39.54MB	39.54MB	0.50MB
datadog-dogstatsd-arm64-deb	0.00MB	✅	37.99MB	37.99MB	0.50MB
datadog-heroku-agent-amd64-deb	0.00MB	✅	440.86MB	440.86MB	0.50MB
datadog-iot-agent-amd64-deb	0.00MB	✅	62.14MB	62.14MB	0.50MB
datadog-iot-agent-x86_64-rpm	0.00MB	✅	62.21MB	62.21MB	0.50MB
datadog-iot-agent-x86_64-suse	0.00MB	✅	62.20MB	62.20MB	0.50MB
datadog-iot-agent-arm64-deb	0.00MB	✅	59.36MB	59.36MB	0.50MB
datadog-iot-agent-aarch64-rpm	0.00MB	✅	59.43MB	59.43MB	0.50MB

Decision

✅ Passed

[agent-platform-auto-pr]

Test changes on VM

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

dda inv aws.create-vm --pipeline-id=57963859 --os-family=ubuntu

Note: This applies to commit a61cf7b

[cit-pr-commenter]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: 322bc37a-eea1-47a1-8c75-b74a9b7fba1d

Baseline: c0121d2
Comparison: a61cf7b
Diff

Optimization Goals: ✅ No significant changes detected

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	+1.69	[+0.80, +2.58]	1	Logs
➖	quality_gate_idle	memory utilization	+1.29	[+1.23, +1.35]	1	Logs bounds checks dashboard
➖	tcp_syslog_to_blackhole	ingress throughput	+0.47	[+0.40, +0.54]	1	Logs
➖	quality_gate_idle_all_features	memory utilization	+0.31	[+0.28, +0.34]	1	Logs bounds checks dashboard
➖	file_to_blackhole_1000ms_latency_linear_load	egress throughput	+0.31	[-0.16, +0.78]	1	Logs
➖	file_to_blackhole_500ms_latency	egress throughput	+0.06	[-0.71, +0.84]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	+0.01	[-0.74, +0.76]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	-0.00	[-0.02, +0.02]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	-0.01	[-0.29, +0.28]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	-0.01	[-0.67, +0.66]	1	Logs
➖	file_to_blackhole_300ms_latency	egress throughput	-0.01	[-0.64, +0.62]	1	Logs
➖	file_to_blackhole_0ms_latency_http1	egress throughput	-0.01	[-0.79, +0.77]	1	Logs
➖	file_to_blackhole_0ms_latency_http2	egress throughput	-0.02	[-0.78, +0.74]	1	Logs
➖	file_tree	memory utilization	-0.03	[-0.08, +0.02]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	-0.22	[-1.00, +0.56]	1	Logs
➖	quality_gate_logs	% cpu utilization	-0.53	[-3.45, +2.39]	1	Logs

Bounds Checks: ✅ Passed

perf	experiment	bounds_check_name	replicates_passed	links
✅	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	lost_bytes	10/10
✅	file_to_blackhole_500ms_latency	memory_usage	10/10
✅	quality_gate_idle	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_idle	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_idle_all_features	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_idle_all_features	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_logs	intake_connections	10/10
✅	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_idle_all_features, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_idle_all_features, 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, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• 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.

[spikat]

Should we use directly cgroup_context_t instead of container_context_t now?

[lebauce]

I suggest to do this in a follow up PR as it will make the PR very noisy

[agent-platform-auto-pr]

Static quality checks ✅

Please find below the results from static quality gates

Successful checks

Info

Result	Quality gate	On disk size	On disk size limit	On wire size	On wire size limit
✅	static_quality_gate_agent_deb_amd64	788.6MiB	801.8MiB	192.33MiB	202.62MiB
✅	static_quality_gate_agent_deb_arm64	779.98MiB	793.14MiB	174.25MiB	184.51MiB
✅	static_quality_gate_agent_rpm_amd64	788.61MiB	801.79MiB	194.31MiB	205.03MiB
✅	static_quality_gate_agent_rpm_arm64	779.95MiB	793.09MiB	175.87MiB	186.44MiB
✅	static_quality_gate_agent_suse_amd64	788.61MiB	801.81MiB	194.31MiB	205.03MiB
✅	static_quality_gate_agent_suse_arm64	780.01MiB	793.14MiB	175.87MiB	186.44MiB
✅	static_quality_gate_dogstatsd_deb_amd64	37.71MiB	47.67MiB	9.78MiB	19.78MiB
✅	static_quality_gate_dogstatsd_deb_arm64	36.3MiB	46.27MiB	8.48MiB	18.49MiB
✅	static_quality_gate_dogstatsd_rpm_amd64	37.71MiB	47.67MiB	9.79MiB	19.79MiB
✅	static_quality_gate_dogstatsd_suse_amd64	37.71MiB	47.67MiB	9.79MiB	19.79MiB
✅	static_quality_gate_iot_agent_deb_amd64	59.33MiB	69.0MiB	14.91MiB	24.8MiB
✅	static_quality_gate_iot_agent_deb_arm64	56.69MiB	66.4MiB	12.86MiB	22.8MiB
✅	static_quality_gate_iot_agent_rpm_amd64	59.33MiB	69.0MiB	14.93MiB	24.8MiB
✅	static_quality_gate_iot_agent_rpm_arm64	56.69MiB	66.4MiB	12.87MiB	22.8MiB
✅	static_quality_gate_iot_agent_suse_amd64	59.33MiB	69.0MiB	14.93MiB	24.8MiB
✅	static_quality_gate_docker_agent_amd64	873.37MiB	886.12MiB	293.87MiB	304.21MiB
✅	static_quality_gate_docker_agent_arm64	887.93MiB	900.79MiB	280.1MiB	290.47MiB
✅	static_quality_gate_docker_agent_jmx_amd64	1.05GiB	1.06GiB	368.98MiB	379.33MiB
✅	static_quality_gate_docker_agent_jmx_arm64	1.05GiB	1.06GiB	351.18MiB	361.55MiB
✅	static_quality_gate_docker_dogstatsd_amd64	45.86MiB	55.78MiB	17.3MiB	27.28MiB
✅	static_quality_gate_docker_dogstatsd_arm64	44.47MiB	54.45MiB	16.17MiB	26.16MiB
✅	static_quality_gate_docker_cluster_agent_amd64	265.09MiB	274.78MiB	106.42MiB	116.28MiB
✅	static_quality_gate_docker_cluster_agent_arm64	281.01MiB	290.82MiB	101.21MiB	111.12MiB