@Override
    public void close(Channels channels) {
        lock.lock();
        try {
            this.running = false;
            for (ConsumerThread consumerThread : consumerThreads) {
                consumerThread.shutdown();
            }
        } finally {
            lock.unlock();
        }
    }
if consumerThreads.length < channelSize
each consumer will process several channels.

if consumerThreads.length == channelSize
each consumer will process one channel.

if consumerThreads.length > channelSize
there will be some threads do nothing.
oap-server/server-library/library-datacarrier-queue/src/main/java/org/apache/skywalking/oap/server/library/datacarrier/consumer/ConsumeDriver.java