enhancement(splunk_hec_metrics sink): Comply to *EventsDropped instrumentation spec in splunk_hec_metrics sink

[pablosichert]

Closes #14213.

Part of #13995.

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Soak Test Results

Baseline: 5149fef
Comparison: e0bbe14
Total Vector CPUs: 4

Explanation

A soak test is an integrated performance test for vector in a repeatable rig, with varying configuration for vector. What follows is a statistical summary of a brief vector run for each configuration across SHAs given above. The goal of these tests are to determine, quickly, if vector performance is changed and to what degree by a pull request. Where appropriate units are scaled per-core.

The table below, if present, lists those experiments that have experienced a statistically significant change in their throughput performance between baseline and comparision SHAs, with 90.0% confidence OR have been detected as newly erratic. Negative values mean that baseline is faster, positive comparison. Results that do not exhibit more than a ±8.87% change in mean throughput are discarded. An experiment is erratic if its coefficient of variation is greater than 0.3. The abbreviated table will be omitted if no interesting changes are observed.

No interesting changes in throughput with confidence ≥ 90.00% and absolute Δ mean >= ±8.87%:

Fine details of change detection per experiment.

experiment	Δ mean	Δ mean %	confidence	baseline mean	baseline stdev	baseline stderr	baseline outlier %	baseline CoV	comparison mean	comparison stdev	comparison stderr	comparison outlier %	comparison CoV	erratic	declared erratic
syslog_regex_logs2metric_ddmetrics	548.48KiB	4.52	100.00%	11.84MiB	962.97KiB	19.62KiB	0	0.0793978	12.38MiB	676.88KiB	13.81KiB	0	0.0533937	False	False
http_pipelines_blackhole_acks	24.6KiB	1.99	100.00%	1.21MiB	122.12KiB	2.48KiB	0	0.0987201	1.23MiB	46.1KiB	963.11B	0	0.0365371	False	False
splunk_hec_route_s3	95.99KiB	0.53	84.24%	17.81MiB	2.33MiB	48.5KiB	0	0.130824	17.9MiB	2.27MiB	47.53KiB	0	0.126912	False	False
datadog_agent_remap_datadog_logs_acks	139.59KiB	0.22	77.09%	62.23MiB	3.4MiB	71.02KiB	0	0.0546117	62.36MiB	4.41MiB	91.78KiB	0	0.0706875	False	False
syslog_splunk_hec_logs	23.34KiB	0.14	74.89%	16.39MiB	779.94KiB	15.87KiB	0	0.0464613	16.41MiB	623.68KiB	12.72KiB	0	0.0371011	False	False
http_to_http_acks	14.21KiB	0.08	4.85%	17.26MiB	7.76MiB	162.19KiB	0	0.449439	17.27MiB	8.06MiB	168.2KiB	0	0.466298	True	True
splunk_hec_to_splunk_hec_logs_noack	16.29KiB	0.07	83.31%	23.82MiB	468.95KiB	9.57KiB	0	0.0192199	23.84MiB	336.93KiB	6.88KiB	0	0.0137998	False	False
splunk_hec_to_splunk_hec_logs_acks	8.9KiB	0.04	27.86%	23.74MiB	883.2KiB	17.96KiB	0	0.0363165	23.75MiB	851.85KiB	17.33KiB	0	0.0350147	False	False
splunk_hec_indexer_ack_blackhole	10.23KiB	0.04	28.96%	23.73MiB	968.97KiB	19.7KiB	0	0.0398596	23.74MiB	945.85KiB	19.24KiB	0	0.0388924	False	False
enterprise_http_to_http	-1.23KiB	-0.01	13.45%	23.85MiB	248.84KiB	5.08KiB	0	0.0101884	23.84MiB	253.38KiB	5.19KiB	0	0.0103751	False	False
syslog_log2metric_humio_metrics	-7.95KiB	-0.06	40.70%	12.67MiB	386.59KiB	7.89KiB	0	0.0297856	12.66MiB	620.03KiB	12.62KiB	0	0.0478013	False	False
file_to_blackhole	-75.31KiB	-0.08	53.46%	95.34MiB	3.23MiB	66.94KiB	0	0.0338632	95.27MiB	3.78MiB	78.49KiB	0	0.0396293	False	False
http_pipelines_blackhole	-1.6KiB	-0.1	38.68%	1.65MiB	59.21KiB	1.21KiB	0	0.0351317	1.64MiB	144.12KiB	2.94KiB	0	0.0855946	False	False
http_to_http_json	-26.64KiB	-0.11	97.49%	23.85MiB	333.11KiB	6.8KiB	0	0.0136387	23.82MiB	476.84KiB	9.75KiB	0	0.0195452	False	False
syslog_humio_logs	-26.55KiB	-0.16	100.00%	16.12MiB	221.44KiB	4.52KiB	0	0.0134136	16.09MiB	198.68KiB	4.07KiB	0	0.0120541	False	False
syslog_log2metric_splunk_hec_metrics	-34.43KiB	-0.19	83.79%	17.63MiB	876.78KiB	17.84KiB	0	0.0485489	17.6MiB	834.02KiB	16.97KiB	0	0.0462698	False	False
datadog_agent_remap_blackhole_acks	-124.88KiB	-0.2	69.15%	60.36MiB	4.71MiB	98.16KiB	0	0.0780774	60.23MiB	3.51MiB	73.49KiB	0	0.0583223	False	False
http_to_http_noack	-70.72KiB	-0.29	99.88%	23.84MiB	404.8KiB	8.28KiB	0	0.0165798	23.77MiB	988.52KiB	20.14KiB	0	0.0406054	False	False
datadog_agent_remap_datadog_logs	-253.27KiB	-0.39	99.52%	63.1MiB	553.39KiB	11.34KiB	0	0.0085622	62.86MiB	4.27MiB	88.97KiB	0	0.0679592	False	False
fluent_elasticsearch	-372.15KiB	-0.46	100.00%	79.47MiB	54.67KiB	1.1KiB	0	0.000671697	79.11MiB	3.98MiB	81.85KiB	0	0.0503462	False	False
datadog_agent_remap_blackhole	-288.2KiB	-0.48	99.25%	58.87MiB	4.06MiB	84.46KiB	0	0.0688671	58.59MiB	3.21MiB	66.92KiB	0	0.0547587	False	False
socket_to_socket_blackhole	-237.63KiB	-1.06	100.00%	21.9MiB	636.83KiB	13.0KiB	0	0.028394	21.67MiB	622.14KiB	12.7KiB	0	0.0280365	False	False
http_pipelines_no_grok_blackhole	-130.78KiB	-1.18	100.00%	10.81MiB	270.17KiB	5.51KiB	0	0.0244027	10.68MiB	1.09MiB	22.75KiB	0	0.102274	False	False
http_text_to_http_json	-491.24KiB	-1.24	100.00%	38.78MiB	1.26MiB	26.32KiB	0	0.0324599	38.31MiB	1.25MiB	26.11KiB	0	0.032584	False	False
syslog_loki	-290.92KiB	-1.97	100.00%	14.45MiB	490.04KiB	10.04KiB	0	0.0331018	14.17MiB	826.25KiB	16.8KiB	0	0.056932	False	False