thanos-io/thanos · error

invalid ResultsCache config

Error message

invalid ResultsCache config

What it means

This is the wrapper message produced by errors.Wrap(err, "invalid ResultsCache config") inside queryrange Config.Validate when the nested ResultsCacheConfig.Validate fails. The final error text is "invalid ResultsCache config: <underlying reason>", e.g. an unsupported compression value or the cache-queryable-samples-stats combination error.

Solutions

  1. Read the wrapped cause after the colon — fix the underlying ResultsCacheConfig issue (e.g. compression value)
  2. Validate the results-cache section independently against supported values
  3. Align flags referenced by nested validation (per-step-stats-enabled, cache config backends)

Example fix

# before
querier:
  results-cache:
    compression: gzip
# after
querier:
  results-cache:
    compression: snappy
Defensive patterns

Strategy: try-catch

Try / catch

if err := cfg.Validate(qCfg); err != nil {
	var wrapped error
	if errors.As(err, &wrapped) || strings.Contains(err.Error(), "invalid ResultsCache config") {
		log.Errorf("results cache section invalid: %v", errors.Unwrap(err))
	}
}

Prevention

When it happens

Trigger: Calling queryrange Config.Validate with cache_results=true and any invalid nested results-cache setting: bad compression, cache-queryable-samples-stats without per-step stats, or invalid embedded CacheConfig.

Common situations: Compound config validation failures at startup where the root cause is in the results-cache section; debugging sessions that only see the wrapper unless the full wrapped error chain is logged.

Understand the failure class

Background: "Invalid value" and "allowed values are" config errors: what your library rejected and how to fix it — this error's family across 41 libraries.

Related errors

AI-assisted analysis of thanos-io/thanos@35b8b99117 (2026-09-07). Data as JSON: /api/errors/48202c138df04fb9. Report an issue: GitHub.

Appendix: source

Thrown at internal/cortex/querier/queryrange/roundtrip.go:75

type Config struct {
	SplitQueriesByInterval time.Duration `yaml:"split_queries_by_interval"`
	AlignQueriesWithStep   bool          `yaml:"align_queries_with_step"`
	ResultsCacheConfig     `yaml:"results_cache"`
	CacheResults           bool `yaml:"cache_results"`
	MaxRetries             int  `yaml:"max_retries"`
	ShardedQueries         bool `yaml:"parallelise_shardable_queries"`
	// List of headers which query_range middleware chain would forward to downstream querier.
	ForwardHeaders flagext.StringSlice `yaml:"forward_headers_list"`
}

// Validate validates the config.
func (cfg *Config) Validate(qCfg querier.Config) error {
	if cfg.CacheResults {
		if cfg.SplitQueriesByInterval <= 0 {
			return errors.New("querier.cache-results may only be enabled in conjunction with querier.split-queries-by-interval. Please set the latter")
		}
		if err := cfg.ResultsCacheConfig.Validate(qCfg); err != nil {
			return errors.Wrap(err, "invalid ResultsCache config")
		}
	}
	return nil
}

// HandlerFunc is like http.HandlerFunc, but for Handler.
type HandlerFunc func(context.Context, Request) (Response, error)

// Do implements Handler.
func (q HandlerFunc) Do(ctx context.Context, req Request) (Response, error) {
	return q(ctx, req)
}

// Handler is like http.Handle, but specifically for Prometheus query_range calls.
type Handler interface {
	Do(context.Context, Request) (Response, error)
}

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