Hi, >this is the first time I have posted to this or any other discussion >group. Apologies if I am not following correct protocol, hopefully >someone will correct me if that is the case.
Don't worry about it ;) The posts that piss people off are ones like "URGENT!!!! MY SERVLET IS NOT WORKING!! PLEASE HELP BECAUSE MY BOSS SAYS IT HAS TO WORK BY 30 MINUTES FROM NOW!" ;) Yours is just about the opposite. >circumstances leave us no choice. This is a very heavily used >application, it has over 120,000 registered users and regularly handles >over 2,000 concurrent users. That's impressive -- cool. >The Java heap size is set to a minimum of 512M and a max of 1024M. That's pretty amazing, 1024 / 2000 = 0.51MB per user, very low per user memory usage. >I would be very grateful for answers to the following questions. > 1. Why was 4.0.5 able to detect these errors while 4.1.24 ignored >them, are they changes to the JSP / Servlet specs or are they bugs? They are not changes to the Spec: Tomcat 4.0 and 4.1 implement the same version of the Servlet (2.3) and JSP (1.1) specifications. However, generally speaking, the later the Tomcat version, the more rigorous the spec implementation is. > 2. Why was performance and stability so much worse with 4.1.24, have >we missed some additional configuration changes that are required or is >4.1 just worse than 4.0. My guess is that two things happened: one, your configuration was incorrect or sub-optimal. Numerous attribute names changed between 4.0 and 4.1, and so simply copying (or copy/pasting relevant sections) server.xml is not that best approach. The second thing is that you went from using the old HTTP/1.1 connector to using the Coyote HTTP/1.1 connector. The latter is the default for Tomcat 4.1 and later. If you want to stick with 4.1.24, you can still use the old HTTP/1.1 connector by changing the className attribute of the Connector element(s) in server.xml appropriately. > 3. Are these problems general to all versions of 4.1 or is 4.1.24 >just a bad release? 4.1.24 is not a terrible release, but by now it's fairly old. There has been work done and bugs fixed on the Tomcat 4.1 branch that are relevant to Connector performance under load. Therefore, if you're going to use Tomcat 4.1, I suggest using the latest stable release, which is 4.1.31 -- a full seven releases' worth of fixes and improvements over 4.1.24. >The Apache Tomcat pages advise users to upgrade to version 5, following >our experiences trying to go to 4.1 we don't feel confident at all about >trying to move to version 5. That's like saying that when trading your 1993 car for a 1997 model you ran into some problems, so you won't trade it in for a 2003 either. It's your call obviously, and either way you should continue your unit, functional, and when possible load testing, but you should definitely upgrade to 5.x. The stability and performance under load are improved. Yoav This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
