/**
 * Reset the accounting on Read and Write.
 *
 * @param newLastTime the milliseconds unix timestamp that we should be considered up-to-date for.
 */
synchronized void resetAccounting(long newLastTime) {
    //interval为什么每次要重新计算？看起来它是固定的，其实不一定，因为我们是固定时间间隔，所以可能会因为具体定时任务稍微单位几个毫秒
    long interval = newLastTime - lastTime.getAndSet(newLastTime);
    if (interval == 0) {
        // nothing to do
        return;
    }
    if (logger.isDebugEnabled() && interval > checkInterval() << 1) {
        logger.debug("Acct schedule not ok: " + interval + " > 2*" + checkInterval() + " from " + name);
    }
    lastReadBytes = currentReadBytes.getAndSet(0);
    lastWrittenBytes = currentWrittenBytes.getAndSet(0);
    lastReadThroughput = lastReadBytes * 1000 / interval;// lastReadThroughput 是使用秒作为单位
    // nb byte / checkInterval in ms * 1000 (1s)
    lastWriteThroughput = lastWrittenBytes * 1000 / interval;
    // nb byte / checkInterval in ms * 1000 (1s)
    realWriteThroughput = realWrittenBytes.getAndSet(0) * 1000 / interval;
    lastWritingTime = Math.max(lastWritingTime, writingTime);
    lastReadingTime = Math.max(lastReadingTime, readingTime);
}