gastownhall/beads · error

acquire connection for compact: %w

Error message

acquire connection for compact: %w

What it means

DoltStore.Compact pins one pooled connection because the versioncontrolops.Compact implementation runs session-scoped DOLT_ stored procedures. This error wraps a failure to acquire that connection from the pool, so the squash of old Dolt commits never starts. The real cause (timeout, canceled context, pool exhaustion) is wrapped via %w.

Source

Thrown at internal/storage/dolt/store.go:2922

// Flatten squashes all Dolt commit history into a single commit.
// Pins a single connection because the stored procedures (DOLT_CHECKOUT,
// DOLT_RESET, etc.) rely on session-scoped state that would be lost if
// steps execute on different pooled connections.
func (s *DoltStore) Flatten(ctx context.Context) error {
	conn, err := s.db.Conn(ctx)
	if err != nil {
		return fmt.Errorf("acquire connection for flatten: %w", err)
	}
	defer conn.Close()
	return versioncontrolops.Flatten(ctx, conn)
}

// Compact squashes old Dolt commits while preserving recent ones.
// Pins a single connection for session-scoped stored procedures.
func (s *DoltStore) Compact(ctx context.Context, initialHash, boundaryHash string, oldCommits int, recentHashes []string) error {
	conn, err := s.db.Conn(ctx)
	if err != nil {
		return fmt.Errorf("acquire connection for compact: %w", err)
	}
	defer conn.Close()
	return versioncontrolops.Compact(ctx, conn, initialHash, boundaryHash, oldCommits, recentHashes)
}

// UnderlyingDB returns the underlying *sql.DB connection
func (s *DoltStore) UnderlyingDB() *sql.DB {
	return s.db
}

// =============================================================================
// Version Control Operations (Dolt-specific extensions)
// =============================================================================

func (s *DoltStore) commitAuthorString() string {
	return fmt.Sprintf("%s <%s>", s.committerName, s.committerEmail)
}

View on GitHub (pinned to 71377f2769)

Solutions

1. Inspect the wrapped error chain to distinguish pool exhaustion from context cancellation from driver failure.
2. Ensure all pinned-connection users (Flatten/Compact/commit paths) close connections promptly; leaks exhaust the pool and surface here.
3. Re-run Compact with a longer context timeout and during a quieter window of concurrent activity.
4. Confirm database connectivity and credentials if the wrapped error indicates the server is unreachable.

// before calling Compact
if err := ctx.Err(); err != nil { return err }
stats := db.Stats()
if stats.MaxOpenConnections > 0 && stats.InUse >= stats.MaxOpenConnections { /* wait or back off */ }

err := store.Compact(ctx, init, boundary, old, recent)
if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
	// reschedule with longer timeout
}

When it happens

Trigger: Calling DoltStore.Compact when db.Conn(ctx) returns an error: no free connection in the pool within the context deadline, context canceled, or driver-level connection failure.

Common situations: Compacting history while many other operations hold pinned sessions; a background compaction job scheduled with a too-short timeout; CI environments where the Dolt process was torn down between steps.

Related errors

• acquire connection for gc: %w
• acquire connection for remote-ref prune: %w
• acquire connection for flatten: %w
• failed to acquire connection: %w
• ErrTransaction

AI-assisted analysis of gastownhall/beads@71377f2769 (2026-08-30). Data as JSON: /api/errors/c2b1ebe3386887ad. Report an issue: GitHub.