select {
		case <-ctx.Done():
			doneCh <- ctx.Err()
			return
		default:
		}

		bucket, ok := z.nextRebalBucket(poolIdx)
		if !ok {
			// no more buckets to rebalance or target free_space/capacity reached
			break
		}

		stopFn := globalRebalanceMetrics.log(rebalanceMetricRebalanceBucket, poolIdx, bucket)
		if err = z.rebalanceBucket(ctx, bucket, poolIdx); err != nil {
			stopFn(err)