![Arthas](https://arthas.aliyun.com/doc/_images/arthas.png) `Arthas` is a Java diagnostic tool open-sourced by Alibaba middleware team. Arthas helps developers in trouble-shooting issues in production environment for Java based applications without modifying code or restarting servers. This tutorial takes a simple application as an example to demonstrate the the usage of `vmtool`. * Github: https://github.com/alibaba/arthas * Docs: https://arthas.aliyun.com/doc/en