AdguardTeam/AdGuardHome · error

putting unit to database: %w

Error message

putting unit to database: %w

What it means

After encoding, putting the unit's bytes into the bbolt bucket failed; wrapped as 'putting unit to database'.

Source

Thrown at internal/stats/unit.go:359

// flushUnitToDB puts udb to the database at id.
func (s *StatsCtx) flushUnitToDB(udb *unitDB, tx *bbolt.Tx, id uint32) (err error) {
	s.logger.Debug("flushing unit", "id", id, "req_num", udb.NTotal)

	bkt, err := tx.CreateBucketIfNotExists(idToUnitName(id))
	if err != nil {
		return fmt.Errorf("creating bucket: %w", err)
	}

	buf := &bytes.Buffer{}
	err = gob.NewEncoder(buf).Encode(udb)
	if err != nil {
		return fmt.Errorf("encoding unit: %w", err)
	}

	err = bkt.Put([]byte{0}, buf.Bytes())
	if err != nil {
		return fmt.Errorf("putting unit to database: %w", err)
	}

	return nil
}

func convertTopSlice(a []countPair) (m []map[string]uint64) {
	m = make([]map[string]uint64, 0, len(a))
	for _, it := range a {
		m = append(m, map[string]uint64{it.Name: it.Count})
	}

	return m
}

// pairsGetter is a signature for topsCollector argument.
type pairsGetter func(u *unitDB) (pairs []countPair)

// topsCollector collects statistics about highest values from the given *unitDB

View on GitHub (pinned to b41aefbe51)

Solutions

1. Reduce the stats data volume or increase available disk/space for the transaction
2. Verify no concurrent Close/reset while flushing
3. Batch or trim oversized units before flush

if err := s.Close(); err != nil { log.Printf("persist failed: %v", err) }

When it happens

Trigger: bkt.Put failing due to a read-only transaction, transaction too large (exceeds bbolt/disk limits), or the DB being closed/corrupted during flush.

Common situations: Very large stats units (huge transaction), disk full, or races between flush and Close/clear.

Related errors

• opening database: %w
• opening a transaction: %w
• opening transaction: %w
• closing database: %w
• creating bucket: %w

AI-assisted analysis of AdguardTeam/AdGuardHome@b41aefbe51 (2026-08-27). Data as JSON: /api/errors/6c9349fe77fc6430. Report an issue: GitHub.