[USM] Enhance USM debugging: add netstat command

[amitslavin]

What does this PR do?

1. Enhanced usm sysinfo command - Now displays detected service names alongside process information
2. New usm netstat command - Shows network connections similar to netstat -antpu with process information

usm sysinfo Enhancements

• Added "Service" column showing detected service names
• Detects DD_SERVICE environment variable from Docker containers and Kubernetes pods
• Falls back to generated service names using the same logic as process-agent
• Added --max-service-length flag (default: 20) to control service name display width
• Refactored to use service discovery infrastructure (envs.Variables, kernel.HostProc())
• Removed all magic numbers and strings, replaced with well-named constants

New usm netstat Command

• Displays active network connections (TCP/UDP, IPv4/IPv6)
• Maps connections to processes showing PID and process name
• Supports filtering: --tcp/-t, --udp/-u, --listening/-l flags
• Shows connection state (ESTABLISHED, LISTEN, TIME_WAIT, etc.)
• Optimized inode-to-PID mapping for performance
• Uses kernel.HostProc() for proper container/namespace support

Motivation

When debugging USM issues, these commands provide essential diagnostic information:

For usm sysinfo:

• Verify service discovery is working correctly for target applications
• Confirm expected services are running and properly identified
• Validate service names match what's expected in USM monitoring
• Debug DD_SERVICE environment variable propagation in containers

For usm netstat:

• Identify which processes own specific network connections
• Debug USM connectivity issues
• Verify which processes are listening on ports
• Check established connections for monitored services
• Troubleshoot port conflicts

Describe how you validated your changes

Manual Testing:

• Verified DD_SERVICE detection from Docker containers (-e DD_SERVICE=mysrv)
• Tested netstat with various flags (--tcp, --udp, --listening)
• Confirmed TCP state display (TIME_WAIT, ESTABLISHED, etc.)
• Validated process name and PID mapping for network connections

Testing:

• Added unit test for --max-service-length flag (default: 20)

Additional Notes

[agent-platform-auto-pr]

Static quality checks

✅ Please find below the results from static quality gates
Comparison made with ancestor 207f856
📊 Static Quality Gates Dashboard

Successful checks

Info

	Quality gate	Delta	On disk size (MiB)	Delta	On wire size (MiB)
✅	agent_deb_amd64	$${+0.04}$$	$${708.37}$$ < $${708.41}$$	$${-0.02}$$	$${173.89}$$ < $${174.49}$$
✅	agent_deb_amd64_fips	$${+0.03}$$	$${703.65}$$ < $${704.0}$$	$${-0.01}$$	$${172.65}$$ < $${173.75}$$
✅	agent_heroku_amd64	$${+0.03}$$	$${328.86}$$ < $${329.53}$$	$${+0.01}$$	$${87.46}$$ < $${88.45}$$
✅	agent_msi	$${+0.01}$$	$${570.99}$$ < $${982.08}$$	$${+0.02}$$	$${142.77}$$ < $${143.02}$$
✅	agent_rpm_amd64	$${+0.04}$$	$${708.35}$$ < $${708.38}$$	$${-0.02}$$	$${176.35}$$ < $${177.66}$$
✅	agent_rpm_amd64_fips	$${+0.03}$$	$${703.63}$$ < $${703.99}$$	$${-0.04}$$	$${175.83}$$ < $${176.6}$$
✅	agent_rpm_arm64	$${+0.02}$$	$${689.9}$$ < $${693.52}$$	$${+0.04}$$	$${160.05}$$ < $${161.26}$$
✅	agent_rpm_arm64_fips	$${+0.03}$$	$${686.02}$$ < $${688.48}$$	$${+0.01}$$	$${159.41}$$ < $${160.55}$$
✅	agent_suse_amd64	$${+0.04}$$	$${708.35}$$ < $${708.38}$$	$${-0.02}$$	$${176.35}$$ < $${177.66}$$
✅	agent_suse_amd64_fips	$${+0.03}$$	$${703.63}$$ < $${703.99}$$	$${-0.04}$$	$${175.83}$$ < $${176.6}$$
✅	agent_suse_arm64	$${+0.02}$$	$${689.9}$$ < $${693.52}$$	$${+0.04}$$	$${160.05}$$ < $${161.26}$$
✅	agent_suse_arm64_fips	$${+0.03}$$	$${686.02}$$ < $${688.48}$$	$${+0.01}$$	$${159.41}$$ < $${160.55}$$
✅	docker_agent_amd64	$${+0.04}$$	$${770.16}$$ < $${770.72}$$	$${+0.02}$$	$${261.8}$$ < $${262.45}$$
✅	docker_agent_arm64	$${+0.02}$$	$${776.26}$$ < $${780.2}$$	$${+0}$$	$${250.84}$$ < $${252.63}$$
✅	docker_agent_jmx_amd64	$${+0.04}$$	$${961.03}$$ < $${961.6}$$	$${-0}$$	$${330.43}$$ < $${331.08}$$
✅	docker_agent_jmx_arm64	$${+0.02}$$	$${955.86}$$ < $${959.8}$$	$${-0}$$	$${315.46}$$ < $${317.27}$$
✅	docker_cluster_agent_amd64	$${+0.02}$$	$${180.74}$$ < $${181.08}$$	$${-0.01}$$	$${63.84}$$ < $${64.49}$$
✅	docker_cluster_agent_arm64	$${+0.06}$$	$${196.62}$$ < $${198.49}$$	$${+0.02}$$	$${60.14}$$ < $${61.17}$$
✅	docker_cws_instrumentation_amd64	$${-0}$$	$${7.13}$$ < $${7.18}$$	$${-0}$$	$${2.99}$$ < $${3.33}$$
✅	docker_cws_instrumentation_arm64	$${0}$$	$${6.69}$$ < $${6.92}$$	$${-0}$$	$${2.73}$$ < $${3.09}$$
✅	docker_dogstatsd_amd64	$${0}$$	$${38.81}$$ < $${39.38}$$	$${-0}$$	$${15.02}$$ < $${15.82}$$
✅	docker_dogstatsd_arm64	$${0}$$	$${37.13}$$ < $${37.94}$$	$${+0}$$	$${14.34}$$ < $${14.83}$$
✅	dogstatsd_deb_amd64	$${0}$$	$${30.03}$$ < $${30.61}$$	$${-0}$$	$${7.94}$$ < $${8.79}$$
✅	dogstatsd_deb_arm64	$${0}$$	$${28.18}$$ < $${29.11}$$	$${-0}$$	$${6.82}$$ < $${7.71}$$
✅	dogstatsd_rpm_amd64	$${0}$$	$${30.03}$$ < $${30.61}$$	$${-0}$$	$${7.95}$$ < $${8.8}$$
✅	dogstatsd_suse_amd64	$${0}$$	$${30.03}$$ < $${30.61}$$	$${-0}$$	$${7.95}$$ < $${8.8}$$
✅	iot_agent_deb_amd64	$${+0.04}$$	$${43.01}$$ < $${43.29}$$	$${+0.01}$$	$${11.26}$$ < $${12.04}$$
✅	iot_agent_deb_arm64	$${+0.03}$$	$${40.13}$$ < $${40.92}$$	$${+0.01}$$	$${9.63}$$ < $${10.45}$$
✅	iot_agent_deb_armhf	$${+0.04}$$	$${40.71}$$ < $${41.03}$$	$${+0.01}$$	$${9.83}$$ < $${10.62}$$
✅	iot_agent_rpm_amd64	$${+0.04}$$	$${43.01}$$ < $${43.29}$$	$${+0.01}$$	$${11.28}$$ < $${12.06}$$
✅	iot_agent_suse_amd64	$${+0.04}$$	$${43.01}$$ < $${43.29}$$	$${+0.01}$$	$${11.28}$$ < $${12.06}$$

[cit-pr-commenter]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: d1fb0d16-1d75-41a1-99a5-79ae2de3898f

Baseline: 876e309
Comparison: 3914a4c
Diff

Optimization Goals: ✅ No significant changes detected

Experiments ignored for regressions

Regressions in experiments with settings containing erratic: true are ignored.

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	docker_containers_cpu	% cpu utilization	+1.16	[-1.84, +4.16]	1	Logs

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	docker_containers_cpu	% cpu utilization	+1.16	[-1.84, +4.16]	1	Logs
➖	ddot_metrics	memory utilization	+0.88	[+0.66, +1.10]	1	Logs
➖	otlp_ingest_metrics	memory utilization	+0.67	[+0.51, +0.82]	1	Logs
➖	quality_gate_idle	memory utilization	+0.54	[+0.50, +0.59]	1	Logs bounds checks dashboard
➖	tcp_syslog_to_blackhole	ingress throughput	+0.43	[+0.37, +0.50]	1	Logs
➖	quality_gate_metrics_logs	memory utilization	+0.32	[+0.10, +0.53]	1	Logs bounds checks dashboard
➖	file_tree	memory utilization	+0.31	[+0.26, +0.36]	1	Logs
➖	ddot_logs	memory utilization	+0.22	[+0.15, +0.28]	1	Logs
➖	quality_gate_idle_all_features	memory utilization	+0.18	[+0.14, +0.21]	1	Logs bounds checks dashboard
➖	ddot_metrics_sum_cumulativetodelta_exporter	memory utilization	+0.13	[-0.10, +0.36]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	+0.06	[-0.34, +0.47]	1	Logs
➖	ddot_metrics_sum_cumulative	memory utilization	+0.04	[-0.12, +0.21]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	-0.00	[-0.08, +0.07]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	-0.01	[-0.13, +0.11]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	-0.01	[-0.43, +0.42]	1	Logs
➖	uds_dogstatsd_to_api_v3	ingress throughput	-0.02	[-0.15, +0.12]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	-0.06	[-0.11, -0.01]	1	Logs
➖	file_to_blackhole_500ms_latency	egress throughput	-0.07	[-0.44, +0.30]	1	Logs
➖	docker_containers_memory	memory utilization	-0.09	[-0.16, -0.02]	1	Logs
➖	uds_dogstatsd_20mb_12k_contexts_20_senders	memory utilization	-0.33	[-0.38, -0.27]	1	Logs
➖	otlp_ingest_logs	memory utilization	-0.64	[-0.73, -0.54]	1	Logs
➖	ddot_metrics_sum_delta	memory utilization	-0.64	[-0.84, -0.44]	1	Logs
➖	quality_gate_logs	% cpu utilization	-1.49	[-2.95, -0.03]	1	Logs bounds checks dashboard

Bounds Checks: ✅ Passed

perf	experiment	bounds_check_name	replicates_passed	links
✅	docker_containers_cpu	simple_check_run	10/10
✅	docker_containers_memory	memory_usage	10/10
✅	docker_containers_memory	simple_check_run	10/10
✅	file_to_blackhole_0ms_latency	lost_bytes	10/10
✅	file_to_blackhole_0ms_latency	memory_usage	10/10
✅	file_to_blackhole_1000ms_latency	lost_bytes	10/10
✅	file_to_blackhole_1000ms_latency	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_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	bounds checks dashboard
✅	quality_gate_logs	lost_bytes	10/10	bounds checks dashboard
✅	quality_gate_logs	memory_usage	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	cpu_usage	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	intake_connections	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	lost_bytes	10/10	bounds checks dashboard
✅	quality_gate_metrics_logs	memory_usage	10/10	bounds checks dashboard

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, 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 lost_bytes: 10/10 replicas passed. Gate passed.
• quality_gate_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check memory_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check cpu_usage: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check intake_connections: 10/10 replicas passed. Gate passed.
• quality_gate_metrics_logs, bounds check lost_bytes: 10/10 replicas passed. Gate 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.

[guyarb]

I think we can remove this option, and the additional code for it
running system-probe usm netstat | grep -i listening yields the same output

[amitslavin]

The --listening flag:

• Shows TCP connections in LISTEN state
• Shows ALL UDP sockets (UDP is connectionless, so there's no "listening" vs "established" concept)
• Filters at the data level before output

Using grep -i listening:

• Only shows output lines containing the text "LISTEN" or "listening"
• Would miss all UDP sockets (their state is "-", not "LISTEN")
• Filters at the text output level

Example difference:

With --listening flag
sudo system-probe usm netstat --listening
tcp | 0.0.0.0:22 | 0.0.0.0:0 | LISTEN | 1234/sshd
tcp | 0.0.0.0:80 | 0.0.0.0:0 | LISTEN | 5678/nginx
udp | 0.0.0.0:53 | 0.0.0.0:0 | - | 9012/dnsmasq # UDP included!

With grep
sudo system-probe usm netstat | grep -i listen
tcp | 0.0.0.0:22 | 0.0.0.0:0 | LISTEN | 1234/sshd
tcp | 0.0.0.0:80 | 0.0.0.0:0 | LISTEN | 5678/nginx
UDP socket is MISSING because it doesn't have "LISTEN" in the output!

The --listening flag follows standard netstat -l behavior and is useful for finding what services are accepting connections

[guyarb]

since --listening is just doing a filtering, you can use grep for it
grep -i -e listening -e udp

The point is that you don't need to actually implement that filtering logic since you can use grep
But that's up to you

[guyarb]

/merge

[dd-devflow-routing-codex]

View all feedbacks in Devflow UI.

2026-01-04 16:04:00 UTC ℹ️ Start processing command /merge

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2026-01-04 16:04:04 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in main is approximately 56m (p90).

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2026-01-04 16:38:43 UTC ℹ️ MergeQueue: This merge request was merged