Thread Dump是什么？

A Java thread dump is the one of the traces/dumps that JVM provides to help diagnosis a hang, deadlock, or monitor contention issue. It contains diagnostic information related to the JVM and a Java application captured at a point during execution. For example, the information can be a list of all the threads that run on a Java virtual machine. Usually thread dumps have more than just thread information. Thread dumps can produce information about the operating system, application environment, threads, stacks, locks, and memory.

注意事项

Thread Dump 时的注意事项：

1. 不同的JAVA虚拟机的Thread Dump的创建方法和文件格式是不一样的，不同的JVM版本， dump信息也有差别。

2. 单独一次的thread dump的信息，通常不足以确认问题。实际使用时建议连续收集三次dump信息，以排除偶然情况。