performance problem when running java applications overnight
From: york (ilcunl_at_yahoo.com)
Date: 15 Oct 2004 05:16:03 -0700
I'm having problems with Java applications that I use and develop on
Windows systems (I have seen on XP and Win2k, not sure if the same
problem exists under Linux). What happens is that I use the
applications all day long and then go home at night. I leave my
computer running and I may or may not minimize the various
application. At night, the computer remains running but idle with
the console locked (doesn't go into standby or spin down harddrives--I
know, waste of electrity but it is company policy so that the
virus-scan/backups can occur).
The next morning I come in and find that each of the java applications
is very sluggish. This sluggishness continues for several minutes at
which times the applications begin responding more normally. All
other applications (firefox, thunderbird, Windows explorer, etc...)
run normally with no performance problems.
Pentium4, 2.2GHz, 1GB RAM, WinXP + SP2 + all patches, dual-monitor
1600x1200x32@85 Hz (GeForce2 MX 400 & GeForce4 MX 440). During
problem, I had about 400MB of free memory (was using 600MB).
Running JBuilder 2005 under JRE 1.4.2_05, Windows LAF.
Returning to work, I unlocked my console. I had the application
minimized so I performed a "restore" to bring it back to it's
maximized state. A solid-gray window was painted onto my primary
monitor. It stayed gray for about 5-10 seconds and then the GUI
repainted. I then clicked on the Project menu. Nothing happened for
about 5-10 seconds and then I got the gray background of the menu drop
down which a few seconds later painted to show the menu choices.
Next I went to the Help menu and went to the About dialog.
Performance was fine doing that. I then went back to the Project menu
to click on it. This time, the Project menu drew it's gray background
immediately then things hung for well over 2 minutes. I didn't have
the bright idea of bringing up the task manager to see if the jbuilder
process was taking up CPU cycles so I don't know what it was doing. I
do know that every other application on my computer was responsive and
fast during this time. Eventually the menu painted the menu options
and everything is working perfectly fast now.
So what was JBuilder doing? This happens to me every morning so I
know that there is a problem. I searched and searched for someone
with this question but nobody else seems to be complaining. Am I the
only one seeing this?
Second application: my own. This swing application runs under JRE5
(1.5.0). It also uses the Windows LAF. When I restored that
application this morning, I got pretty much identical symptoms to what
I got with JBuilder - namely the application restored to the screen
(not maximized in this case) by rendering a gray rectangle to the
screen. The actual GUI did not paint for about 5-10 seconds. Then
various actions in the GUI were very sluggish for the first several
minutes of use and then magically things sped up to normal speed.
This is not a new problem- I've seen this problem as far back as I can
recall. Several times I've gotten fed up and done a search both on
usenet and on Sun's java site but I can never find anybody complaining
about this problem. I'd hate for my users to experience this problem
with my application.
Any ideas? I'm hoping there is some JVM tuning I can do to
minimize/eliminate this problem?
Thanks for your help!