Grouper Users - Open Discussion List

[Chris Hyzer <>]

When to restart the app server is a little tricky.  Hibernate and cglib 
complicate matters (among other libraries).  They sometimes do something 
where when you hot-reload a java webapp, the old one doesn't get released 
from memory.  Do a few reloads, and you will be out of memory.

There used to be a few posts on the hibernate forum about this, but they look 
like they are gone.  Here is a post which scratches the surface:

http://forum.hibernate.org/viewtopic.php?t=941783&highlight=tomcat+memory+restart

Anyways, I like to restart the app server when reloading an app.  Due to 
this, I run each app on its own tomcat.  Tomcat is pretty lightweight, and we 
run dozens of tomcats on the same server (sharing the same common files so we 
only have a couple of tomcat versions) and it scales great.  It also means a 
memory leak or a permgen problem in one app doesn't affect other apps.  Of 
course, it helps to have scripts to manage this (Penn has 60 java webapps, 
load balanced on 4-7 servers, which means ~300 tomcats running...  you need 
automation and monitoring here).  Of course other people might have good luck 
with hot swap and running multiple apps in one app server (if you pay for an 
appserver, it will be more likely to work :) ).

In any case, I added this to the quickstart readme faq:

The build scripts can restart tomcat if configured correctly.  Whenever you 
do a build/release to tomcat or an app server, it is probably a good idea to 
make sure the app server (e.g. tomcat) is restarted (either manually or with 
ant), though refer to your app server's documentation and do restart if there 
are problems.

Regards,
Chris

> -----Original Message-----
> From: Aaron Fuleki 
> [mailto:]
> Sent: Wednesday, December 03, 2008 4:11 PM
> To: Tom Barton
> Cc: 
> 
> Subject: Re: [grouper-users] problems with 1.4.0 RC1 quickstart
>
> Hmm... restarting tomcat fixed things - I'm not sure why.  Maybe I
> started things in the wrong order, and the db wasn't available?  I
> don't think the readme explicitly states when to start tomcat, unless
> I glossed over it.
>
> Anyways, I have success!
>
> -Aaron
>
> ---------------------------------
> Aaron Fuleki
> Web Services Manager
> Denison University
> 740.587.5752
> ---------------------------------
>
>
> On Dec 3, 2008, at 3:17 PM, Tom Barton wrote:
>
> > That will happen if the database connection failed to be
> > established. Were there other messages in grouper_error.log? If not,
> > try upping the log level for the log4j.logger.net.sf.hibernate
> > logger to info (in grouper/conf/log4j.properties) and rerun to see
> > what further details it provides.
> >
> > Tom
> >
> > Aaron Fuleki wrote:
> >> Hey folks,
> >>   I just tried running the 1.4.0 RC1 quickstart, with a fresh
> >> Tomcat 5.5.27 download on my Macbook Pro (10.5.5), and keep getting
> >> this in the error log:
> >> ERROR actions.PopulateErrorAction: < -
> >> C409BD757393C4C8A7BB7ED754FF9489-0004 - - - > Caught '500' for /
> >> grouper/populateIndex.do
> >> The builds went fine, and tomcat and hsqldb start right up, but I
> >> get that error and my web browser just says:
> >> Error:
> >>    * The error has been logged and the administrator notified.
> >>    * If you continue to encounter errors, please contact technical
> >> support.
> >> Any ideas? Is it trying to populate the sample data and borking?
> >> Thanks!
> >> -Aaron
> >> ---------------------------------
> >> Aaron Fuleki
> >> Web Services Manager
> >> Denison University
> >> 740.587.5752
> >> ---------------------------------
> >