@Override
        public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
            Long now = System.nanoTime();
            Channel child = (Channel) msg;
            child.attr(CONN_DIMENSIONS).set(Attrs.newInstance());
            ConnTimer timer = ConnTimer.install(child, registry, registry.createId("zuul.conn.client.timing"));
            timer.record(now, "ACCEPT");
            ConnCounter.install(child, registry, registry.createId("zuul.conn.client.current"));
            super.channelRead(ctx, msg);
        }
Keys should be a short string usable in metrics.
zuul-core/src/main/java/com/netflix/zuul/netty/server/Server.java