cachebench: observation %d has invalid optimizer identity

Error message

cachebench: observation %d has invalid optimizer identity

What it means

Error "cachebench: observation %d has invalid optimizer identity" thrown in JuliusBrussee/caveman.

Source

Thrown at cacheengine/cachebench/observed.go:212

	seen := make(map[string]bool, len(records))
	for index, record := range records {
		if record.Schema != ObservationSchema && record.Schema != ObservationSchemaV2 {
			return fmt.Errorf("cachebench: observation %d schema %q", index, record.Schema)
		}
		if !validBoundedText(record.RequestID, 512, false) || seen[record.RequestID] {
			return fmt.Errorf("cachebench: observation %d empty or duplicate request_id", index)
		}
		seen[record.RequestID] = true
		if !validBoundedText(record.Provider, 64, false) || !validBoundedText(record.Epoch, 1024, false) || !validBoundedText(record.QualityVerifier, 256, false) || !validBoundedText(record.ProfileID, 256, true) || !validBoundedText(record.EngineReason, 1024, true) || !validEvidenceSHA256(record.ProviderEvidenceSHA256) || !validEvidenceSHA256(record.QualityEvidenceSHA256) {
			return fmt.Errorf("cachebench: observation %d missing provider or quality evidence provenance", index)
		}
		if record.RequestBodySHA256 != "" && !validSHA256(record.RequestBodySHA256) {
			return fmt.Errorf("cachebench: observation %d has invalid request body digest", index)
		}
		optimizerIDs := map[string]bool{}
		for _, optimizerID := range record.OptimizerIDs {
			if !validBoundedText(optimizerID, 256, false) || optimizerIDs[optimizerID] {
				return fmt.Errorf("cachebench: observation %d has invalid optimizer identity", index)
			}
			optimizerIDs[optimizerID] = true
		}
	}
	return nil
}

func validSHA256(value string) bool {
	return len(value) == 64 && strings.Trim(value, "0123456789abcdef") == ""
}

func validEvidenceSHA256(value string) bool {
	return validSHA256(value) && value != bodyDigest(nil)
}

func evaluateObservedProvider(provider string, records []ObservationRecord, target Target) ProviderReport {
	report := ProviderReport{Provider: provider, Model: "observed", Rolling: true, EvaluatedRequests: len(records)}
	qualityPasses := 0

View on GitHub (pinned to 27d5a3981a)

Solutions

Fix the optimizer identity in the observation.

When it happens

Trigger: Thrown at cacheengine/cachebench/observed.go:212 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of JuliusBrussee/caveman@27d5a3981a (2026-08-15). Data as JSON: /api/errors/1a88345a345a568d. Report an issue: GitHub.