Valuethreshold %d greater than max batch size of %d. Either

Error message

Valuethreshold %d greater than max batch size of %d. Either reduce opt.ValueThreshold or increase opt.BaseTableSize.

What it means

Transaction writes are batched to at most opt.maxBatchSize bytes, which is derived from MemTableSize (15%). If ValueThreshold exceeds maxBatchSize, every large value would exceed the batch budget and transactions could never push data, so Open() fails fast.

Source

Thrown at db.go:172

	opt.maxBatchSize = (15 * opt.MemTableSize) / 100
	opt.maxBatchCount = opt.maxBatchSize / int64(skl.MaxNodeSize)

	// This is the maximum value, vlogThreshold can have if dynamic thresholding is enabled.
	opt.maxValueThreshold = math.Min(maxValueThreshold, float64(opt.maxBatchSize))
	if opt.VLogPercentile < 0.0 || opt.VLogPercentile > 1.0 {
		return errors.New("vlogPercentile must be within range of 0.0-1.0")
	}

	// We are limiting opt.ValueThreshold to maxValueThreshold for now.
	if opt.ValueThreshold > maxValueThreshold {
		return fmt.Errorf("Invalid ValueThreshold, must be less or equal to %d",
			maxValueThreshold)
	}

	// If ValueThreshold is greater than opt.maxBatchSize, we won't be able to push any data using
	// the transaction APIs. Transaction batches entries into batches of size opt.maxBatchSize.
	if opt.ValueThreshold > opt.maxBatchSize {
		return fmt.Errorf("Valuethreshold %d greater than max batch size of %d. Either "+
			"reduce opt.ValueThreshold or increase opt.BaseTableSize.",
			opt.ValueThreshold, opt.maxBatchSize)
	}
	// ValueLogFileSize should be strictly LESS than 2<<30 otherwise we will
	// overflow the uint32 when we mmap it in OpenMemtable.
	if !(opt.ValueLogFileSize < 2<<30 && opt.ValueLogFileSize >= 1<<20) {
		return ErrValueLogSize
	}

	if opt.ReadOnly {
		// Do not perform compaction in read only mode.
		opt.CompactL0OnClose = false
	}

	needCache := (opt.Compression != options.None) || (len(opt.EncryptionKey) > 0)
	if needCache && opt.BlockCacheSize == 0 {
		panic("BlockCacheSize should be set since compression/encryption are enabled")
	}

View on GitHub (pinned to 2a001d466f)

Solutions

Reduce opt.ValueThreshold below opt.maxBatchSize
Increase opt.MemTableSize so that 15% of it exceeds ValueThreshold
Follow the error's advice: reduce ValueThreshold or increase BaseTableSize

Example fix

// before
opt.MemTableSize = 8 << 20 // 8MB, maxBatchSize ~1.2MB
opt.ValueThreshold = 4 << 20 // 4MB > batch size -> error
// after
opt.MemTableSize = 64 << 20
opt.ValueThreshold = 4 << 20 // now under maxBatchSize (~9.6MB)

Defensive patterns

Strategy: validation

Validate before calling

maxBatch := (15 * opt.MemTableSize) / 100
if opt.ValueThreshold > maxBatch {
    return fmt.Errorf("lower ValueThreshold (<%d) or raise MemTableSize", maxBatch)
}

Prevention

Derive ValueThreshold from MemTableSize in config code
Test Open() with production options in CI
Document the 15% maxBatchSize rule next to your option setters

When it happens

Trigger: Calling badger.Open with opt.ValueThreshold greater than (15*MemTableSize)/100, e.g. a large ValueThreshold (like 1MB) combined with a small MemTableSize.

Common situations: Raising ValueThreshold without checking MemTableSize; shrinking BaseTableSize/MemTableSize for tests while keeping production ValueThreshold.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

AI-assisted analysis of dgraph-io/badger@2a001d466f (2026-09-05). Data as JSON: /api/errors/da61246cd2bbcc58. Report an issue: GitHub.