java start options

java 启动参数 

  1. OOME 时生成堆 dump
      -XX:+HeapDumpOnOutOfMemoryError 
    
  2. jdwp 协议 远程调试模式
     -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=9999
        #### 早期版本
      -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=9999
    
  3. **常用分析工具
    1. ha heap analysis
    2. jca java core analysis
    3. ga gc log analysis