OpenTelemetry TraceIdRatioBased sampler requirements following OTEP 235

[jmacd]

Fixes #1413.

Changes

Updates Trace SDK and TraceState handling specifications with OTEP 235 sampling thresholds. This PR depends on https://github.com/open-telemetry/opentelemetry-specification/pull/4162 to introduce the concept of Trace Randomness. This PR is the second part of two, it focuses on thresholds.

• Revise TraceIdRatioBased algorithm section. The existing TODO implies this is not a breaking change.
• Change text about TraceIdRatioBased construction
• Move text about TraceIdRatioBased description (leave unmodified).

The content of OTEP 235 was revised for clarity by @kalyanaj in https://github.com/open-telemetry/oteps/pull/261. I've heavily copied from the final text in that still-unmerged OTEP. I introduced new content explaining how to compute thresholds from probabilities with use of variable precision, referring to the OTel Collector-Contrib pkg/sampling reference implementation. The new (Golang) demonstration code is validated here, https://go.dev/play/p/7eLM6FkuoA5.

A proof of concept for this specification along with #4162 can be found in https://github.com/open-telemetry/opentelemetry-go/pull/5645.

Part of #3602.

Product of the Sampling SIG members @kentquirk @kalyanaj @oertl @PeterF778 and myself.

• [x] Related issues also #3307, #2253, #2179, #2113, #1947,#1844
• [x] OTEP: https://github.com/open-telemetry/oteps/pull/235
• [x] Links to the prototypes: https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/processor/probabilisticsamplerprocessor, https://github.com/open-telemetry/opentelemetry-go/pull/5645
• [x] CHANGELOG.md
• [x] spec-compliance-matrix.md

[stazz]

FWIW, it seems that this bug has been fixed in otel-collector v.1.32.0 🤔

[colinbjohnson]

Note that this appears to be fixed in public.ecr.aws/aws-observability/aws-otel-collector:v0.42.0 but I wanted to provide instructions for reproducing/testing the bug anyway.

---

To reproduce this issue in either public.ecr.aws/aws-observability/aws-otel-collector:v0.41.2 or public.ecr.aws/aws-observability/aws-otel-collector:v0.41.1 you can do the following:

# create an otel-agent-config.yaml file
cat > otel-agent-config.yaml <<EOF
services:
  aws-ot-collector:
    image: public.ecr.aws/aws-observability/aws-otel-collector:v0.41.2
    command: ["--config=/etc/otel-agent-config.yaml"]
    volumes:
      - ./otel-agent-config.yaml:/etc/otel-agent-config.yaml
    ports:
      - 4318:4318
EOF
cat > docker-compose.yaml <<EOF
services:
  aws-ot-collector:
    image: public.ecr.aws/aws-observability/aws-otel-collector:v0.41.2
    command: ["--config=/etc/otel-agent-config.yaml"]
    volumes:
      - ./otel-agent-config.yaml:/etc/otel-agent-config.yaml
    ports:
      - 4318:4318
EOF
# and run docker
docker compose up

Once the OTEL container is running:

curl http://localhost:4318

Even though this is not an actual metric send this will create the given bug.

[github-actions[bot]]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 30 days.

[colinbjohnson]

This issue is not stale. The problem still exists.

[colinbjohnson]

@pawelkaliniakit - I believe that this issue has been resolved by newer versions of the aws-otel-collector - if this is true you might consider marking this issue closed.

[github-actions[bot]]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 30 days.

[github-actions[bot]]

This issue was closed because it has been marked as stale for 30 days with no activity.