JVM参数意义及默认值

http://www.blogjava.net/midstr/archive/2008/09/21/230265.html
http://jiajun.iteye.com/blog/443196


sun 官方文档 http://download.oracle.com/javase/1.5.0/docs/tooldocs/share/jstat.html

形象解释:
http://www.hh010.com/developer/html/43-4/4227.htm