// expand and then we continue to rebalance.
func (z *erasureServerPools) updateRebalanceStats(ctx context.Context) error {
	var ok bool
	for i := range z.serverPools {
		if z.findIndex(i) == -1 {
			// Also ensure to initialize rebalanceStats to indicate
			// its a new pool that can receive rebalanced data.
			z.rebalMeta.PoolStats = append(z.rebalMeta.PoolStats, &rebalanceStats{})
			ok = true
		}