pendingSize     int64
	failedSize      int64
	replicaSize     int64
	replicaCount    int64
	pendingCount    uint64
	failedCount     uint64
	replTargetStats map[string]replTargetSizeSummary
	tiers           map[string]tierStats
}

// replTargetSizeSummary holds summary of replication stats by target
type replTargetSizeSummary struct {
	replicatedSize  int64
	replicatedCount int64
	pendingSize     int64