One more thing to try is to have a limit on you users' requests. All the tuning in the world will not help if you are letting your users run amok in the system. The same thing happened to us with Tomcat killing our server and causing daily crashes. When I got to this job, there were no restriction on server things. The culprits were the lack of restrictions on "Max entries Returned by Getlist" and Allow Unqualified Search was set. Here's what you want to look at : - You need to go to AR System Administration\Server Information \Configuration - Make Sure that "Max Entries Returned by Getlist" is not 0. I set it to 10000 and that seems to work fine. Any less that that will cause AR system to become unstable. - Uncheck "Allow Unqualified Searches" if it is checked. - Enable Persistent Cache on your Mid-Tier Configuration tool. This helps keep memory utilization lower by having Tomcat go to the Cache instead of the DB every time a form is called.
If you you don't take care of these issues what will happen is that a user can do a full scan query on a form and that causes a huge chunk of your available Tomcat Memory to be taken up by the Getlist call (method). Sometimes the memory is not returned due to no caching or a memory leak. If you restrict your users, you will not be using up as much Tomcat memory. I tried to tune my garbage collection and this helped a lot. But in the end the mid-tier would crash with an java out of memory error. I turned on Thread logging (also in AR system Admin) and whenever I saw a crash I could find the query that crashed Tomcat. Thread logging should show you how big the chunk is that is getting called. I hope this helps, Jesus Ortega ITSM Technologist LyondellBasell Industries Office: 713 309-4914 Cell: 281 546-0735 From: Action Request System discussion list(ARSList) [mailto:[email protected]] On Behalf Of Rick Sharp Sent: Thursday, December 15, 2011 8:56 AM To: [email protected] Subject: ARS Tomcat Slowdowns are Crippling Us......HELP ! ** Hi All We have a new ARS 7.604 instance with incredible slow MidTier performance every 3 days. Tomcat sucks up 3GB+ RAM and 53% CPU (today) and cripples the MidTier. Restart Tomcat and all is fine for 2 days. Unacceptable to our 200 IT users and is killing us. Our base of 4800 end users touches Remedy via our Kinetic front end, which is never an issue; just the MidTier for IT Staff. Any help is much appreciated !!!! Specifics: We are running Tomcat for ARS and Tomcat for Kinetic, as separate services. The ARS Tomcat runs away with Memory and cripples us at 3GB, while CPU is fine with its service. Kinetic's Tomcat is fine. IBM x3650 VM for MidTier as well as ARS **SQL is hosted on a separate W2K8 VM Windows 2008 x64 bit Quad Zeon 2.26GHz 6GB RAM J2SE Dev Kit 5.0 Update 22 J2SE Runtime Environment 5.0 Update 22 Java 6 Update 27 x64 bit Java 7 Update 1 Java SE DevKit 6 Update 27 x64 bit _attend WWRUG12 www.wwrug.com<http://www.wwrug.com> ARSlist: "Where the Answers Are"_ Information contained in this email is subject to the disclaimer found by clicking on the following link: http://www.lyondellbasell.com/Footer/Disclaimer/ _______________________________________________________________________________ UNSUBSCRIBE or access ARSlist Archives at www.arslist.org attend wwrug12 www.wwrug12.com ARSList: "Where the Answers Are"
