OTLP Trace — 60-Way Parallel Fan-Out (json)
One root span with 60 overlapping children — a scatter-gather query across database shards. The counterpart to the deep-chain fixture: shallow but very wide, which is what breaks waterfall layouts that assume spans do not overlap in time.
{
"resourceSpans": [
{
"resource": {
"attributes": [
{
"key": "service.name",
"value": {
"stringValue": "checkout-api"
}
},
{
"key": "service.namespace",
"value": {
"stringValue": "shop"
}
},
{
"key": "service.version",
"value": {
"stringValue": "1.14.2"
}
},
{
"key": "service.instance.id",
"value": {
"stringValue": "checkout-api-7d9f4c-2xk"
}
},
{
"key": "deployment.environment.name",
"value": {
"stringValue": "staging"
}
},
{
"key": "host.name",
"value": {
"stringValue": "node-a1"
}
},
{
"key": "host.ip",
"value": {
"stringValue": "192.0.2.11"
}
},
{
"key": "cloud.region",
"value": {Specifications
- Spans
- 61
- Depth
- 2
- Children
- 60
- Shape
- fan-out
- Overlapping
- true
- Root Duration Ms
- 74
Testing contract
Expected to pass- Scenario
- Lay out the trace as a waterfall and compute critical path.
- Expected result
- 60 sibling spans overlap in time under a 74 ms root, and the critical path is the longest child rather than the sum of all children.
What is a .json file?
JSON (JavaScript Object Notation) is a lightweight, text-based data-interchange format representing objects, arrays, strings, numbers, booleans, and null. It is language-independent, human-readable, and the dominant format for web APIs and configuration. It requires a single well-formed root value.
How to use this file
Use an example JSON file to test parsers and serializers, schema validation, Unicode and number-precision handling, and API request or response processing.
How to use this file for testing
“OTLP Trace — 60-Way Parallel Fan-Out (json)” is a deterministic Novus Examples fixture for Observability, JSON parsing, Performance testing. Structured and plain-text telemetry with known timestamps, levels, request identifiers, and error states for testing log ingestion, correlation, dashboards, and alert pipelines.
Documented properties for this file: JSON · 52,360 bytes. Compare results against paired or grouped companions on this page when present (clean↔damaged, searchable↔scanned, or format twins) so scores stay reproducible across runs.
Download the file once, keep the path stable in CI or local scripts, and treat the spec table as the contract: dimensions, seeds, field lists, and roles are intentional. Corrupt or invalid samples are labelled as such — expect parsers to fail loudly rather than silently accept them.
Telemetry fixtures use fixed trace IDs, span IDs, and timestamps so ingestion is reproducible run to run. Point your collector, parser, or query layer at the file and assert the documented span tree, metric families, or severity mix; service and host names are invented.
Code examples
import json
with open("otlp-trace-wide-fanout.json") as f:
data = json.load(f)
print(type(data), len(data))Related files
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