如何在Web应用程序中查找加载页面的cpu，io，内存利用率

Question

I've written a Java file, using Jsp,servlets, that I would like to perform run-time tests on. I've never done this before and was just curious on how to go about it.

What I'm interested in knowing, besides the actual timings, is how to find cpu,memory and io utilization when running the application.Your thoughts are appreciated.

Answer 1

Typically you wouldn't measure these from within the application, but by running another tool on the same host.

If you just want to see the impact on the host operating system, you can use a program like top (on *nix boxes), or good old Task Manager on Windows, to see the CPU/memory/IO utilisation of your Java process (typically the servlet container such as Tomcat).

If you want more detailed information on the actual Java process itself, you can connect JConsole or jvisualvm to get VM information (including memory and CPU) for the process itself. (With Java 6 you should be able to do this from the local machine without passing any parameters to the Java process at startup; for Java 5, or remote connections, you'll need to pass command-line arguments to the Java process to allow (remote) JMX connections.)

Finally, if you want really in-depth details of the resource usage, down to the performance of various methods (which it sounds like you're after), you'll need to use a profiler. There are several of these for Java - with YourKit and JProfiler being the biggest commercial ones (in my unqualified opinion). I believe that the NetBeans IDE also has a decent profiler built-in. The process for connecting these to your application would vary depending on the app itself, but these will all typically allow you to "drill down" into the CPU time to see which classes/methods took the most cycles to execute, and likewise to drill down into memory use to see which classes are taking up the most memory.

Answer 2

The standard way to monitor running Java applications these days is sing JMX through the JConcole

If your a using a commercial application server like Weblogic or WebSphere these have custom and powerful management consoles that provide the monitoring information you are looking for. The technology at the heart of these consoles is still JMX so these can also be monitored and managed using the standard JConsole. This article shows how to do this for Weblogic .

Answer 3

I guess you need this info in the client side (browser). So it's not Java based question.

If so, here is my answer: I prefer using FireBug and ySlow extensions. They give performance information, memory information and much more.

I combine it with using regular task-manager to view more information about the browser.

BR