My feeling is that by calling an installatin of 'java' or 'the jdk/jre' a 'jvm' is going to produce confusion.
/usr/local/applications/tomcat1 /usr/local/applications/tomcat2 /usr/local/applications/tomcat3 /usr/local/java That's one *JDK/JRE*, and 3 tomcat *instances*. Each tomcat startup file uses the same JDK to launch a separate *JVM* (so 3 JVMs equates directly to 3 tomcat instances) because as Leon says, you can't run 2 tomcats in a single JVM. So no need to install java more than once, just launch multiple JVMs (and thus, multiple tomcats). We do this on a single CPU box, because we find we 'need' to manage the memory of the webapps running in each instance. So if we 'need' to bounce a tomcat server because it's got 1% free and isn't getting any better, then we still have the other two tomcats serving the websites they serve. And I always say 'need' in quotes because yes, one day we'll track down our leaks and then we won't 'need' to do that. Of course, we're still CPU-bound, so there's no real 'performance' or 'scalability' enhancement by having more than one instance on a single box. We'd get that (I think) if we clustered more than one physical box each with its own tomcat/jvm instance, or by clustering multiple tomcats on a a single, multiple-cpu box. That last paragraph is my own weak understanding of CPUs/scalability/clustering, so could be off. > -----Original Message----- > From: Biernatowski Bartosz J [mailto:[EMAIL PROTECTED] > Sent: Monday, June 19, 2006 4:55 PM > To: 'Tomcat Users List' > Subject: RE: Tomcat's scalability > > > My understanding of Tomcat's instance is having both > Tomcat+JVM installed in separate directories. Both Tomcats > running on separate ports. > > BJ Biernatowski > Application Developer, e-Business > > -----Original Message----- > From: GB Developer [mailto:[EMAIL PROTECTED] > Sent: Monday, June 19, 2006 2:40 PM > To: 'Tomcat Users List' > Subject: RE: Tomcat's scalability > > How do you propose to add a 'separate instance of Tomcat' > without 'adding a separate JVM'? > > Or do you/others mean by 'instance of tomcat' = 'a separate > physical server with single instance of JVM/Tomcat' ? > > > > > So far it sounds that the approach of adding separate > > instance of Tomcat and using round robin is better than > > adding a separate JVM. > > > > > --------------------------------------------------------------------- > To start a new topic, e-mail: users@tomcat.apache.org > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > > This e-mail, including attachments, may include confidential > and/or proprietary information, and may be used only by the > person or entity to which it is addressed. If the reader of > this e-mail is not the intended recipient or his or her > authorized agent, the reader is hereby notified that any > dissemination, distribution or copying of this e-mail, > including its contents and attachments, is prohibited. If you > have received this e-mail in error, please notify the sender > by a "reply to sender only" message and delete this e-mail > immediately and destroy all electronic and hard copies of the > communication, including attachments. > > > --------------------------------------------------------------------- > To start a new topic, e-mail: users@tomcat.apache.org > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
