Hi Marc, it still sounds like it could be a connection pool issue to me. Which of the available connection pools are you using and how exactly have you set it up in your tomcat config? Maybe we can see something in there.
Cheers, Jan Jan Behrens OFFIS FuE-Bereich Betriebliches Informationsmanagement Escherweg 2 - 26121 Oldenburg - Germany Fon: +49 4 41 97 22 - 187 - Fax: +49 4 41 97 22-102 E-mail: [EMAIL PROTECTED] - URL: http://www.offis.de Marc Richards <[EMAIL PROTECTED]> schrieb am 16.12.2005 06:07:22: > Yes, I agree - I thought that too, but didn't really > know what I was suppose to be seeing. I have Tomcat > configured to open 500 (because I was mucking around > trying to make it work, not because I think that's the > right setting) connections on startup and maintain a > minimum of 100 idle at any time. But when I start > Tomcat I only see a single ESTABLISHED connection to > the db. Then I start jmeter and this list explodes. > > I thought I might be bypassing the connection pool > too, but didn't know how to check that either. We use > the Spring Framework and it has a method for calling > the JNDI pool manager. So you just configure Spring > to obtain new connections from Tomcat and it does the > actual access to the db when an sql is used. The apps > never actually close any connections because Spring is > suppose to do that for you too. There just doesn't > seem to be a way to check that everything is being > done correctly (that I can tell). I can tell you this > though - when I changed the Spring configuration > initially, I forgot to save my changes to the Tomcat > config. Immediately all database connections from the > apps began to fail because the pool manager wasn't > turned on. Then I configured Tomcat and checked in my > changes - it began working again. So I can tell that > Spring is relying on Tomcat's ability to connect to > the db, but I can't tell that it's using it correctly. > > It seems to me that Spring is using JNDI to obtain a > connection, doing a read and then leaving the line for > dead. The first 500 get used up and then either > Tomcat or the apps themselves begin firing off more. > > Here is a question I probably should have asked first: > When I configure Tomcat to pool connections (let's > say to start up with an initial 50), what should I see > when I run netstat directly after starting Tomcat and > before I make any calls to the web app? Should I see > 50 connections (I don't)? > > -marc > > > > > --- "Caldarale, Charles R" > <[EMAIL PROTECTED]> wrote: > > > > From: "Marc Richards" <[EMAIL PROTECTED]> > > > Subject: Performance degradation under load > > > > > > Tomcat is handling connection pooling to our > > iSeries > > > database server (db2, jdbc), but I'm not sure it's > > > working correctly because when I do netstat I see > > > several thousand db connections sitting at > > TIME_WAIT > > > (presumably abandoned and waiting to be cleaned up > > by > > > the pool manager). > > > > This really sounds like you're not using connection > > pooling, but instead > > are opening a new connection for each request. How > > many do you have > > configured in the pool? If it's less than the > > number you see with > > netstat, that would be another indication that your > > app is getting its > > own connections rather than ones from the pool. > > > > Is your app closing the connections (and statements > > and result sets) > > properly? This usualy requires putting the close > > statements in finally > > blocks, just to make sure that exceptions don't > > cause them to be > > skipped. > > > > - Chuck > > > > > > THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR > > OTHERWISE PROPRIETARY > > MATERIAL and is thus for use only by the intended > > recipient. If you > > received this in error, please contact the sender > > and delete the e-mail > > and its attachments from all computers. > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: > > [EMAIL PROTECTED] > > For additional commands, e-mail: > > [EMAIL PROTECTED] > > > > > > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
