public void process(SocketChannel channel) throws Exception {
		SocketChannel peer = (channel == cliSC)? svrSC: cliSC;
		buf.clear();
		try {
			int size = channel.read(buf);
			checkChannelOp("read", size,channel);
			logger.trace("session {} read data size:{} from {}",id, size, channel);
			buf.flip();
			Thread.sleep(delay);
			size = peer.write(buf);
			checkChannelOp("write", size,peer);
			logger.trace("session {} write data size:{} to {}",id, size, peer);
		} catch (Exception e) {
			cliSC.close();
			svrSC.close();
			logger.debug("session {} is closed", id);
			throw e;
		}

	}