On 21/12/2010 23:49, George Sexton wrote: >> -----Original Message----- >> From: Caldarale, Charles R [mailto:chuck.caldar...@unisys.com] >> Sent: Monday, December 20, 2010 1:08 PM >> To: Tomcat Users List >> Subject: Re: IS that a good idea moving all the common libs? >> >> On Dec 20, 2010, at 12:16, "Luca Gervasi" <tom...@ashetic.net> wrote: >> >>> I'm trying to lower the permgen needed by a large amount of webapps >>> moving all the commonly used libs to the tomcat common libs. >> >> That's a really, really bad idea. You would be intertwining all your >> webapps, potentially introducing object leaks across webapps, and >> creating insurmountable versioning issues. You'd also require a >> complete Tomcat restart to update any single webapp. > > I'm really not seeing that. Anyhow, would the suggestion change if you were > running 300+ web applications?
It is do-able if you are prepared to accept the associated constraints: - all web apps must use the exact same version of every shared library - updating the shared libraries requires a Tomcat restart - all of the shared web apps must be "well behaved" in a multiple class-loader environment - one out of control web application can take down the whole instance If the libraries are well behaved, it is possible to update/reload individual web applications. As the new memory leak detection features are showing, a fair number of libs and applications are not well behaved. Personally, I think those constraints are too much for every web app so I would probably use a mixture of multiple Tomcat instances, self-container web apps and webapps that shared libraries but with a preference for self-contained web apps over shared libraries. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
