add agent doc. #1083

site/src/site/sphinx/advanced-use.md

@@ -91,6 +91,10 @@ Arthas支持使用管道对上述命令的结果进行进一步的处理，如`s
 
 * [Web Console](web-console.md)
 
+## 以java agent方式启动
+
+* [以java agent方式启动](agent.md)
+
 ## 用户数据回报
 
 在`3.1.4`版本后，增加了用户数据回报功能，方便统一做安全或者历史数据统计。

site/src/site/sphinx/agent.md

@@ -0,0 +1,15 @@
+以Java Agent的方式启动
+===
+
+通常Arthas是以动态attach的方式来诊断应用，但从`3.2.0`版本起，Arthas支持直接以 java agent的方式启动。
+
+比如下载全量的arthas zip包，解压之后以 `-javaagent` 的参数指定`arthas-agent.jar`来启动：
+
+```
+java -javaagent:/tmp/test/arthas-agent.jar -jar arthas-demo.jar
+```
+
+默认的配置项在解压目录里的`arthas.properties`文件里。
+
+
+参考： https://docs.oracle.com/javase/8/docs/api/java/lang/instrument/package-summary.html

site/src/site/sphinx/en/advanced-use.md

@@ -86,6 +86,10 @@ Arthas supports living inside a browser. The communication between arthas and br
 
 * [Web Console](web-console.md)
 
+## Start as a Java Agent
+
+* [Start as a Java Agent](agent.md)
+
 ## User data report
 
 After the `3.1.4` version, arthas support user data report.

site/src/site/sphinx/en/agent.md

@@ -0,0 +1,14 @@
+Start as a Java Agent
+====
+
+Usually Arthas dynamic attach the applications on the fly, but from version `3.2.0` onwards, Arthas supports starting directly as a java agent.
+
+For example, download the full arthas zip package, decompress it and start it by specifying `arthas-agent.jar` with the parameter `-javaagent`.
+
+````
+java -javaagent:/tmp/test/arthas-agent.jar -jar arthas-demo.jar
+````
+
+The default configuration is in the `arthas.properties` file in the decompression directory.
+
+Reference: https://docs.oracle.com/javase/8/docs/api/java/lang/instrument/package-summary.html