rebalance

type CheckAndSender interface {
	Check(ctx context.Context, peer string, refs []torus.BlockRef) ([]bool, error)
	PutBlock(ctx context.Context, peer string, ref torus.BlockRef, data []byte) error
}

type Rebalancer interface {
	Tick() (int, error)
	VersionStart() int
	PrepVolume(*models.Volume) error
	Reset() error
}

type Ringer interface {
	Ring() torus.Ring
	UUID() string
}