Option, is an old-generation mark-sweep collector that stops the world briefly for an initial mark phase and again later for a brief re-mark phase and then allows the user program to resume while the garbage collector threads execute concurrently with the user program 选项启用,它是一个老代标记-清除收集器,它在初始标记阶段(及在以后暂短重新标记阶段)暂短地停止整个系统,然后恢复用户程序,同时垃圾收集器线程与用户程序并发地执行。