docs: private final void checkForDeadConnections(final long now) {
          final ArrayList<Pair<Connection, Integer>> connectionsToRemove = new ArrayList<Pair<Connection, Integer>>();
          for (final ClientInterfaceHandleManager cihm : m_cihm.values()) {
              // Internal connections don't implement calculatePendingWriteDelta(), so check for real connection first
              if (VoltPort.class == cihm.connection.getClass()) {
                  final int delta = cihm.connection.writeStream().calculatePendingWriteDelta(now);
                  if (delta > CLIENT_HANGUP_TIMEOUT) {
                      connectionsToRemove.add(Pair.of(cihm.connection, delta));
                  }
              }
          }
  
          for (final Pair<Connection, Integer> p : connectionsToRemove) {
              Connection c = p.getFirst();
              networkLog.warn("Closing connection to " + c +
                      " because it hasn't read a response that was pending for " +  p.getSecond() + " milliseconds");
              c.unregister();
          }
      }