Open Telemetry histograms reporting from otel receiver?

[zeldigas]

I have a question regarding metrics reporting to signal fx.

Template configures receiving otlp data (https://github.com/signalfx/splunk-otel-collector-chart/blob/main/helm-charts/splunk-otel-collector/templates/config/_otel-agent.tpl#L1131) and streaming it to signal fx when special flag enabled https://github.com/signalfx/splunk-otel-collector-chart/blob/main/helm-charts/splunk-otel-collector/templates/config/_otel-agent.tpl#L1168

With this setup I got some strange data for histogram based metrics. Here is example for gc collection in nodejs instrumentation (https://github.com/open-telemetry/opentelemetry-js-contrib/blob/main/packages/instrumentation-runtime-node/src/metrics/gcCollector.ts#L51):

1. v8js.gc.duration_bucket with le attribute. Each metric is a collection of events that are less than configured bucket value
2. v8js.gc.duration_min/max - min max values
3. v8js.gc.duration_sum - sum of values
4. v8js.gc.duration_count - number events

That seems like not a convinient format to wor in signalfx. I don't see so far how to get percentile value from this.

I suspect that this format is reported becasue for signalfx exporter flag to process otlp histograms is disabled: https://github.com/signalfx/splunk-otel-collector-chart/blob/main/helm-charts/splunk-otel-collector/templates/config/_otel-agent.tpl#L943. But there is special flag enabled in signalfx/histograms exporter: https://github.com/signalfx/splunk-otel-collector-chart/blob/main/helm-charts/splunk-otel-collector/templates/config/_otel-agent.tpl#L969

So the question is - is it reporting fine and I need to work with this <metric>_bucket in some special way in signalfx or this combination (otlp metrics + signalfx exporter) does not work properly for histograms and agent need to be reconfigured to use exporter with send_otlp_histograms set to true?