tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Mike Bachrynowski" <>
Subject RE: 100% CPU Usage
Date Fri, 31 Jan 2003 11:01:42 GMT
It depends on how you create the request.  If every request creates a new session and you are
not explicitly killing the sessions and the session time-out is set to 15 minutes then memory
will disappear.  We had affliates using robots to retrieve up to date availability and rate
information.  Each request created a new session (note our servlet server was not Tomcat but
my tests seem to suggest Tomcat behaves the same).  I explicitly killed the session after
outputting the response and problem solved.  With lower transaction volumes GC does eventually
kick in.    In servlet servers you can configure the web app  to do various things the problem
is the application "knows" whether the requester is a registered customer or a robot.  Tomcat
(I may be wrong here) can't be clever enough as this is part of the application logic.  Nobody
likes putting operational code in application code I could see how Tomcat you track and then
use a more intelligent GC algorithm but this would add an overhead and could potentially drop
sessions which needs to be retained.  My feeling is encoding in the application is the only
way at this point.
Comments or thoughts?
I use Apache2 connecting through JK2 to Tomcat4.  I am not using JBoss.

	-----Original Message----- 
	From: [] 
	Sent: Fri 31/01/2003 05:44 
	Subject: 100% CPU Usage

	      We have a application that send request to the server approximtely
	every 1 second. Considering that 2 connectios are made to the server and 1
	request ever 1 second from 2 users its around 2 request every second work
	well for couple of hours. But it seems the GC is never called. After couple
	of hours the server usage 100% CU. This works well for some more time and
	then the srever gets dead slow. What can be the reason and how can we stop
	100% memory usage? There is no databse connection but calls are made to
	JBoss application server for each request that comes. Is this tomcat
	problem if yes is there a workaround?????????
	[ -=-=-=-=-=-=-=-=-=-=-=- Hrishikesh Kamat -=-=-=-=-=-=-=-=-=-=-=- ]
	Trust Your Instincts
	91 20 5511262 - Ext 465
	To unsubscribe, e-mail:
	For additional commands, e-mail:

View raw message