code: func (cn *connection) nominalMaxRequests() (ret int) {
  	if cn.t.requestStrategy == 3 {
  		expectingTime := int64(cn.totalExpectingTime())
  		if expectingTime == 0 {
  			expectingTime = math.MaxInt64
  		} else {
  			expectingTime *= 2
  		}
  		return int(clamp(
  			1,
  			int64(cn.PeerMaxRequests),
  			max(
  				// It makes sense to always pipeline at least one connection,
  				// since latency must be non-zero.
  				2,
  				// Request only as many as we expect to receive in the
  				// dupliateRequestTimeout window. We are trying to avoid having to
  				// duplicate requests.
  				cn.chunksReceivedWhileExpecting*int64(cn.t.duplicateRequestTimeout)/expectingTime,
  			),
  		))
  	}
  	return int(clamp(
  		1,
  		int64(cn.PeerMaxRequests),
  		max(64,
  			cn.stats.ChunksReadUseful.Int64()-(cn.stats.ChunksRead.Int64()-cn.stats.ChunksReadUseful.Int64()))))
  }
docs: // The actual value to use as the maximum outbound requests.