Support Sampling for Long-Duration Span and Erroneous Span

[pepeshore]

Is your feature request related to a problem? Please describe.

100% sampling rate is not suitable for production environments because of high overhead,but non-100% sampling may lead to the loss of certain important spans,such as long-Duration span and erroneous span. I try to provide a custom io.opentelemetry.sdk.trace.SpanProcessor which will hold the spans associated with the same traceId util LocalRootSpan is ended. But I found that when isRecording(samplingDecision) is false, a io.opentelemetry.api.trace.PropagatedSpan is returned instead of io.opentelemetry.sdk.trace.SdkSpan which lost a lot of important information

Describe the solution you'd like

Two solution

1. Return a SDKSpan even if isRecording(samplingDecision) is false, by this, I can give a custom io.opentelemetry.sdk.trace.SpanProcessor to implement Sampling for Long-Duration Span and Erroneous Span
2. if sampling for long-duration span、erroneous span or other span with specified feature is a common need，can the agent give a native support

Describe alternatives you've considered

No response

Additional context

No response

[trask]

hi @pepeshore! have you seen the Collector Tail-Based Sampler?

[pepeshore]

hi @pepeshore! have you seen the Collector Tail-Based Sampler?
yes，it's really a helpful approach, tks