@Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        if (ctx.channel().attr(ATTR_CH_THROTTLED).get() != null) {
            // Discard this msg as channel is in process of being closed.
            ReferenceCountUtil.safeRelease(msg);
        } else {
            super.channelRead(ctx, msg);
        }
    }
Closes any incoming new connections if current count is above a configured threshold.

When a connection is throttled, the channel is closed, and then a CONNECTION_THROTTLED_EVENT event is fired
not notify any other interested handlers.
zuul-core/src/main/java/com/netflix/netty/common/throttle/MaxInboundConnectionsHandler.java