[AGNT-338] Implement eviction logic for pattern

[DDuongNguyen]

Requirements:

1. Get an estimate for the number of distinct patterns we expect enabling patterns to see significant savings for.

a. A superficial investigation to expected usage and savings should be performed on staging.

b. If, for example, we tend to see several orders of magnitude log dropoff after the 10 most common patterns then we might make different thresholds than if we see the same dropoff only after 800 patterns.

2. A reasonable memory threshold must be set for the pattern table and its related components

a. This might take the form of a max count of patterns rather than a byte-sized limit, since we can bound the size of log lines to a known upper value.

3. Sane eviction rules must be established to determine what patterns, if any, should be replaced when the memory threshold is reached

a. count-min sketch? - more memory usage but less likely to cause constant rule flakes

b. smallest count in timeframe? - more memory efficient but more likely to flake on the smallest rule

c. other?

4. Pattern evictions must be communicated to intake and survive connection interruptions just like pattern additions/changes

[agent-platform-auto-pr]

Static quality checks

✅ Please find below the results from static quality gates
Comparison made with ancestor 2bc506d
📊 Static Quality Gates Dashboard

Successful checks

Info

	Quality gate	Change	Size (prev → curr → max)
✅	agent_heroku_amd64	+4.0 KiB (0.00% increase)	326.912 → 326.916 → 329.530
✅	agent_msi	+3.0 KiB (0.00% increase)	571.538 → 571.541 → 982.080

29 successful checks with minimal change (< 2 KiB)

	Quality gate	Current Size
✅	agent_deb_amd64	705.273 MiB
✅	agent_deb_amd64_fips	700.558 MiB
✅	agent_rpm_amd64	705.259 MiB
✅	agent_rpm_amd64_fips	700.544 MiB
✅	agent_rpm_arm64	686.828 MiB
✅	agent_rpm_arm64_fips	682.934 MiB
✅	agent_suse_amd64	705.259 MiB
✅	agent_suse_amd64_fips	700.544 MiB
✅	agent_suse_arm64	686.828 MiB
✅	agent_suse_arm64_fips	682.934 MiB
✅	docker_agent_amd64	767.468 MiB
✅	docker_agent_arm64	773.616 MiB
✅	docker_agent_jmx_amd64	958.346 MiB
✅	docker_agent_jmx_arm64	953.214 MiB
✅	docker_cluster_agent_amd64	180.684 MiB
✅	docker_cluster_agent_arm64	196.557 MiB
✅	docker_cws_instrumentation_amd64	7.135 MiB
✅	docker_cws_instrumentation_arm64	6.689 MiB
✅	docker_dogstatsd_amd64	38.812 MiB
✅	docker_dogstatsd_arm64	37.128 MiB
✅	dogstatsd_deb_amd64	30.031 MiB
✅	dogstatsd_deb_arm64	28.180 MiB
✅	dogstatsd_rpm_amd64	30.031 MiB
✅	dogstatsd_suse_amd64	30.031 MiB
✅	iot_agent_deb_amd64	42.987 MiB
✅	iot_agent_deb_arm64	40.112 MiB
✅	iot_agent_deb_armhf	40.689 MiB
✅	iot_agent_rpm_amd64	42.987 MiB
✅	iot_agent_suse_amd64	42.987 MiB

On-wire sizes (compressed)

	Quality gate	Change	Size (prev → curr → max)
✅	agent_deb_amd64	+19.11 KiB (0.01% increase)	173.310 → 173.329 → 174.490
✅	agent_deb_amd64_fips	+25.46 KiB (0.01% increase)	172.242 → 172.267 → 173.750
✅	agent_heroku_amd64	+18.52 KiB (0.02% increase)	87.094 → 87.112 → 88.450
✅	agent_msi	-36.0 KiB (0.02% reduction)	142.961 → 142.926 → 143.020
✅	agent_rpm_amd64	-7.5 KiB (0.00% reduction)	176.157 → 176.150 → 177.660
✅	agent_rpm_amd64_fips	-28.1 KiB (0.02% reduction)	174.941 → 174.914 → 176.600
✅	agent_rpm_arm64	-4.56 KiB (0.00% reduction)	159.324 → 159.319 → 161.260
✅	agent_rpm_arm64_fips	+8.81 KiB (0.01% increase)	158.762 → 158.771 → 160.550
✅	agent_suse_amd64	-7.5 KiB (0.00% reduction)	176.157 → 176.150 → 177.660
✅	agent_suse_amd64_fips	-28.1 KiB (0.02% reduction)	174.941 → 174.914 → 176.600
✅	agent_suse_arm64	-4.56 KiB (0.00% reduction)	159.324 → 159.319 → 161.260
✅	agent_suse_arm64_fips	+8.81 KiB (0.01% increase)	158.762 → 158.771 → 160.550
✅	docker_agent_amd64	neutral	261.032 MiB
✅	docker_agent_arm64	+3.98 KiB (0.00% increase)	250.042 → 250.046 → 252.630
✅	docker_agent_jmx_amd64	-3.36 KiB (0.00% reduction)	329.674 → 329.671 → 331.080
✅	docker_agent_jmx_arm64	-6.81 KiB (0.00% reduction)	314.683 → 314.676 → 317.270
✅	docker_cluster_agent_amd64	neutral	63.831 MiB
✅	docker_cluster_agent_arm64	neutral	60.120 MiB
✅	docker_cws_instrumentation_amd64	neutral	2.994 MiB
✅	docker_cws_instrumentation_arm64	neutral	2.726 MiB
✅	docker_dogstatsd_amd64	neutral	15.026 MiB
✅	docker_dogstatsd_arm64	neutral	14.351 MiB
✅	dogstatsd_deb_amd64	neutral	7.945 MiB
✅	dogstatsd_deb_arm64	neutral	6.823 MiB
✅	dogstatsd_rpm_amd64	neutral	7.957 MiB
✅	dogstatsd_suse_amd64	neutral	7.957 MiB
✅	iot_agent_deb_amd64	neutral	11.259 MiB
✅	iot_agent_deb_arm64	neutral	9.631 MiB
✅	iot_agent_deb_armhf	neutral	9.823 MiB
✅	iot_agent_rpm_amd64	neutral	11.275 MiB
✅	iot_agent_suse_amd64	neutral	11.275 MiB

[cit-pr-commenter]

Regression Detector

Regression Detector Results

Metrics dashboard
Target profiles
Run ID: 87314ead-72c5-42bd-a1f4-26191d2d4c16

Baseline: 2bc506d
Comparison: 9a9eb73
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	-3.16	[-6.06, -0.26]	1	Logs

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	trials	links
➖	quality_gate_metrics_logs	memory utilization	+1.19	[+0.97, +1.41]	1	Logs bounds checks dashboard
➖	ddot_metrics_sum_cumulative	memory utilization	+0.64	[+0.48, +0.81]	1	Logs
➖	quality_gate_idle	memory utilization	+0.43	[+0.38, +0.47]	1	Logs bounds checks dashboard
➖	ddot_metrics_sum_cumulativetodelta_exporter	memory utilization	+0.39	[+0.16, +0.62]	1	Logs
➖	file_tree	memory utilization	+0.21	[+0.16, +0.27]	1	Logs
➖	otlp_ingest_logs	memory utilization	+0.18	[+0.08, +0.28]	1	Logs
➖	file_to_blackhole_0ms_latency	egress throughput	+0.09	[-0.43, +0.61]	1	Logs
➖	file_to_blackhole_500ms_latency	egress throughput	+0.06	[-0.33, +0.45]	1	Logs
➖	file_to_blackhole_100ms_latency	egress throughput	+0.06	[+0.01, +0.11]	1	Logs
➖	file_to_blackhole_1000ms_latency	egress throughput	+0.03	[-0.38, +0.43]	1	Logs
➖	uds_dogstatsd_to_api_v3	ingress throughput	+0.02	[-0.11, +0.14]	1	Logs
➖	uds_dogstatsd_to_api	ingress throughput	+0.00	[-0.13, +0.13]	1	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	-0.01	[-0.10, +0.09]	1	Logs
➖	docker_containers_memory	memory utilization	-0.01	[-0.08, +0.06]	1	Logs
➖	uds_dogstatsd_20mb_12k_contexts_20_senders	memory utilization	-0.01	[-0.07, +0.04]	1	Logs
➖	ddot_metrics_sum_delta	memory utilization	-0.05	[-0.25, +0.15]	1	Logs
➖	quality_gate_idle_all_features	memory utilization	-0.06	[-0.10, -0.02]	1	Logs bounds checks dashboard
➖	otlp_ingest_metrics	memory utilization	-0.13	[-0.28, +0.02]	1	Logs
➖	ddot_logs	memory utilization	-0.19	[-0.25, -0.12]	1	Logs
➖	tcp_syslog_to_blackhole	ingress throughput	-0.25	[-0.32, -0.17]	1	Logs
➖	ddot_metrics	memory utilization	-0.48	[-0.70, -0.26]	1	Logs
➖	quality_gate_logs	% cpu utilization	-0.70	[-2.16, +0.76]	1	Logs bounds checks dashboard
➖	docker_containers_cpu	% cpu utilization	-3.16	[-6.06, -0.26]	1	Logs

Bounds Checks: ❌ Failed

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	9/10	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".

Replicate Execution Details

We run multiple replicates for each experiment/variant. However, we allow replicates to be automatically retried if there are any failures, up to 8 times, at which point the replicate is marked dead and we are unable to run analysis for the entire experiment. We call each of these attempts at running replicates a replicate execution. This section lists all replicate executions that failed due to the target crashing or being oom killed.

Note: In the below tables we bucket failures by experiment, variant, and failure type. For each of these buckets we list out the replicate indexes that failed with an annotation signifying how many times said replicate failed with the given failure mode. In the below example the baseline variant of the experiment named experiment_with_failures had two replicates that failed by oom kills. Replicate 0, which failed 8 executions, and replicate 1 which failed 6 executions, all with the same failure mode.

Experiment	Variant	Replicates	Failure	Logs	Debug Dashboard
experiment_with_failures	baseline	0 (x8) 1 (x6)	Oom killed		Debug Dashboard

The debug dashboard links will take you to a debugging dashboard specifically designed to investigate replicate execution failures.

❌ Retried Profiling Replicate Execution Failures (target internal profiling)

Note: Profiling replicas may still be executing. See the debug dashboard for up to date status.

Experiment	Variant	Replicates	Failure	Debug Dashboard
quality_gate_idle_all_features	baseline	11 (x4)	Oom killed	Debug Dashboard
quality_gate_idle_all_features	comparison	11 (x3)	Oom killed	Debug Dashboard

CI Pass/Fail Decision

❌ Failed. Some Quality Gates were violated.

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