redis: AutoPipelineOptions.MaxBatchBytes=%d must be >= 0

Error message

redis: AutoPipelineOptions.MaxBatchBytes=%d must be >= 0

What it means

Returned by AutoPipelineOptions.Validate when MaxBatchBytes is negative. Zero is allowed (meaning no byte cap); negative values are rejected as configuration errors. MaxBatchBytes caps a batch by approximate payload volume to avoid huge single writes.

Source

Thrown at autopipeline.go:228

// Validate()==nil does not guarantee construction succeeds: rules that need
// the face (e.g. NumShards>1 requires Unordered on the deferred face) are
// enforced by the AutoPipeline/AsyncAutoPipeline getters. Note also that
// Options.AutoPipelineOptions is validated lazily — on the first getter
// call, not in NewClient.
func (cfg *AutoPipelineOptions) Validate() error {
	if cfg.MaxConcurrentBatches > 1 && !cfg.Unordered {
		return fmt.Errorf("redis: AutoPipelineOptions.MaxConcurrentBatches=%d requires Unordered:true "+
			"(parallel batches do not preserve command ordering); set Unordered:true to allow it, "+
			"or keep MaxConcurrentBatches=1 for an ordered stream", cfg.MaxConcurrentBatches)
	}
	// Reject obviously-wrong negatives so a typo surfaces at construction rather
	// than being silently coerced to a default. Zero is allowed and means "use
	// the default" (MaxBatchSize) or "no delay" (MaxFlushDelay).
	if cfg.MaxBatchSize < 0 {
		return fmt.Errorf("redis: AutoPipelineOptions.MaxBatchSize=%d must be >= 0", cfg.MaxBatchSize)
	}
	if cfg.MaxBatchBytes < 0 {
		return fmt.Errorf("redis: AutoPipelineOptions.MaxBatchBytes=%d must be >= 0", cfg.MaxBatchBytes)
	}
	if cfg.MaxConcurrentBatches < 0 {
		return fmt.Errorf("redis: AutoPipelineOptions.MaxConcurrentBatches=%d must be >= 0", cfg.MaxConcurrentBatches)
	}
	if cfg.MaxFlushDelay < 0 {
		return fmt.Errorf("redis: AutoPipelineOptions.MaxFlushDelay=%s must be >= 0", cfg.MaxFlushDelay)
	}
	if cfg.NumShards < 0 {
		return fmt.Errorf("redis: AutoPipelineOptions.NumShards=%d must be >= 0", cfg.NumShards)
	}
	if cfg.AdaptiveDelay && cfg.MaxFlushDelay <= 0 {
		return fmt.Errorf("redis: AutoPipelineOptions.AdaptiveDelay requires MaxFlushDelay > 0 " +
			"(adaptive delay scales MaxFlushDelay by queue fill; with no MaxFlushDelay it would " +
			"silently disable batch accumulation entirely)")
	}
	return nil
}

View on GitHub (pinned to 36d97525cd)

Solutions

Set MaxBatchBytes to 0 (no byte cap, the default) or a positive byte limit.
Use 0 rather than a negative for 'disabled'.
Sanitize config values before constructing the options.

Example fix

// before
cfg := &redis.AutoPipelineOptions{MaxBatchBytes: -1024}
// cfg.Validate() => error

// after
cfg := &redis.AutoPipelineOptions{MaxBatchBytes: 0}       // no cap
// or
cfg := &redis.AutoPipelineOptions{MaxBatchBytes: 1 << 20} // 1 MiB cap

Defensive patterns

Strategy: validation

Validate before calling

func sanitizeBatchBytes(n int) int {
    if n < 0 {
        return 0 // no byte cap instead of an invalid negative
    }
    return n
}

Try / catch

if err := cfg.Validate(); err != nil {
    if strings.Contains(err.Error(), "MaxBatchBytes") {
        cfg.MaxBatchBytes = 0 // reset to no-cap
    }
}

Prevention

Use 0 for 'no byte cap' MaxBatchBytes, never a negative.
Sanitize config values to >= 0 at load time.
Document 0 as the disabled sentinel in your config schema.

When it happens

Trigger: Setting AutoPipelineOptions.MaxBatchBytes to a negative value. Sign errors or uninitialized config fields producing negatives.

Common situations: Config parsing mistakes. Using a negative sentinel to mean 'disabled' when zero is the documented disabled value. Arithmetic underflow.

Related errors

AI-assisted analysis of go-redis/redis@36d97525cd (2026-08-06). Data as JSON: /data/errors/33dc8ec2aa9822a2.json. Report an issue: GitHub.