If the problem remains a mystery after analyzing the PMI data, a set of thread dumps of the JVM often pinpoints synchronized methods and other common problems.

如果在评测pmi数据以后，仍然没有找到问题所在，JVM的一些线程堆经常能定位同步方法和其他常见问题。

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To do this, we set the thread priority of the polling threads to 38 (the highest RT priority) and the priorities of the triage pool threads to 37.

为此，我们将轮询线程的线程优先级设置为 38（最高的 RT 优先级），将筛选池线程的优先级设置为 37。

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When the synchronization object is used in one of the wait functions, the wait function blocks the calling thread until the state of the synchronized object is set to signaled.

当在一个等待函数中使用同步对象时，等待函数就会阻塞调用线程，直到同步对象的状态被设置为有信号为止。

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So, if you're trying to use Napster to Go with the iRiver H10, and you're seeing the same problem, check out this thread and follow the second set of instructions (there are two on the page) to reformat your player, then re-transfer your NTG files and try again.

ENGADGET: Napster To Go: Review and Features Guide