Tomcat OS mem size / Object mem size discrepencies

Questions about YourKit Java Profiler
Post Reply
nbw
Posts: 5
Joined: Wed Jan 12, 2005 3:42 pm

Tomcat OS mem size / Object mem size discrepencies

Post by nbw »

Hi,

I'm sorry if this is not the correct place to post this question. I did not see a "users" forum.

I've hooked yourkit into my Tomcat - 5.0.28 - service running on Win32 with JDK 1.4.2_05 by adding the yourkit lib -X option to the Tomcat service VM's option line.

I then have a simple class which connects and takes a snap shot, this class is wrapped in script which also gets the memory usage of the tomcat process as reported by Windows (ie Taskmanager).

The interesting thing I am seeing is that the process size of Tomcat is always much larger then Object size reported by the snapshot. For example:

-- Size reported by task manager
2005-01-11 19:09:53: 120868MB

-- Size YourKit reports of snapshot at same time
Profiler>> Classes: 3680 Objects: 426462 ObjSize: 27MB StringSize: 2431KB

As you can see the tomcat process is taking up 120 MB but the ObjSize reported is only 27 MB.

Can anyone shed some light as to what is going on here?

Thanks.
Vladimir Kondratyev
Posts: 1624
Joined: Tue Aug 10, 2004 7:52 pm

Post by Vladimir Kondratyev »

Post Reply