Hi Joe, This is done in the startup of Tomcat by including a startup paramter for java: -Xincgc along with the startup memory and max memory that is defined.
If you are on UNIX you will need to modify your startup.sh file where you have these lines: JAVA_OPTS="$JAVA_OPTS -Xms1536m"; export JAVA_OPTS JAVA_OPTS="$JAVA_OPTS -Xmx2560m"; export JAVA_OPTS to something like JAVA_OPTS="$JAVA_OPTS -Xms1536m"; export JAVA_OPTS JAVA_OPTS="$JAVA_OPTS -Xmx2560m -Xincgc"; export JAVA_OPTS Restart Tomcat after that and then your process should look something like: aradmin 3984 1 70 08:09 pts/1 00:00:11 /apps/ar/jre1.6.0_13/bin/java -Xms1536m -Xmx2560m -Xincgc -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.util.logging.config.file=/apps/ar/tomcat-5.5.25/conf/logging.properties -Djava.endorsed.dirs=/apps/ar/tomcat-5.5.25/common/endorsed -classpath :/apps/ar/tomcat-5.5.25/bin/bootstrap.jar:/apps/ar/tomcat-5.5.25/bin/commons-logging-api.jar -Dcatalina.base=/apps/ar/tomcat-5.5.25 -Dcatalina.home=/apps/ar/tomcat-5.5.25 -Djava.io.tmpdir=/apps/ar/tomcat-5.5.25/temp org.apache.catalina.startup.Bootstrap start Without the incremental garbage collection turned on your process would look like: aradmin 3531 1 0 Jun29 ? 00:04:10 /apps/ar/jre1.6.0_13/bin/java -Xms1536m -Xmx2560m -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.util.logging.config.file=/apps/ar/tomcat-5.5.25/conf/logging.properties -Djava.endorsed.dirs=/apps/ar/tomcat-5.5.25/common/endorsed -classpath :/apps/ar/tomcat-5.5.25/bin/bootstrap.jar:/apps/ar/tomcat-5.5.25/bin/commons-logging-api.jar -Dcatalina.base=/apps/ar/tomcat-5.5.25 -Dcatalina.home=/apps/ar/tomcat-5.5.25 -Djava.io.tmpdir=/apps/ar/tomcat-5.5.25/temp org.apache.catalina.startup.Bootstrap start Are you on UNIX or Windows? The instructions I have given is for UNIX. If you are on windows I think you need to modify your Java Options found in the Java tab of the utility tomcat5w.exe Hope this helps.. Joe ________________________________ From: remedydon <mrohinikanth2...@gmail.com> To: arslist@ARSLIST.ORG Sent: Wednesday, July 15, 2009 7:54:14 PM Subject: Re: Apache Tomcat Memory Pool Hi Joe, "Another useful tip would be to turn on incremental garbage collection. This is always good to free up unused portions of memory that haven't been used for a significant time interval." Where can I find this feature to turn it on ? Joe ________________________________ From: "Begosh, Kevin" <kevin.beg...@lmco.com> To: arslist@ARSLIST.ORG Sent: Tuesday, February 3, 2009 3:14:40 PM Subject: Re: Apache Tomcat Memory Pool ** Yes this does help and I am on 7.1 as well so this would help out a lot. We are having those exact issue with Tomcat crashing. Kevin Begosh, RSP Tech Ops Enterprise Business Services 301-791-3540 Phone 410-422-3623 Cell kevin.beg...@lmco.com From:Action Request System discussion list(ARSList) [mailto:arsl...@arslist.org] On Behalf Of Joe DeSouza Sent: Tuesday, February 03, 2009 1:13 PM To: arslist@ARSLIST.ORG Subject: Re: Apache Tomcat Memory Pool ** Thsi is more of a Tomcat setting than a 'BMC recommended' setting. The golden rule for sizing tomcat memory is to not use more than 65% to 70% of the available free memory before the tomcat service is started. This gives the server at least 30% to 35% headroom. With that in mind it is nice to have a max memory of at least around the 3 GB mark where the usage of the servers is about average. Since you are using tomcat, if you are using Mid-Tier 7.1, I would recommend to hop on the patch 006. In my experience here the earlier patches had a memory issue, that addresses OutOfMemory errors that cause Tomcat to crash which was addressed in Patch 006. Also the performance is way better as I have noticed that it takes a relatively short time for the server to build its cache after an initial restart on patch 006 (at least 5 to 10 times faster) than it was on lets say Patch 003. I haven't tried patches in between 003 and 006 Hope this helps.. Cheers Joe ________________________________ From:"Begosh, Kevin" <kevin.beg...@lmco.com> To: arslist@ARSLIST.ORG Sent: Tuesday, February 3, 2009 12:53:46 PM Subject: Apache Tomcat Memory Pool ** Does anyone know what the BMC recommended or what the best settings are for the Apache Tomcat memory pool for the Mid Tier. We are windows 2003 and we have two mid tiers that are load balanced. Kevin Begosh, RSP Tech Ops Enterprise Business Services 301-791-3540 Phone 410-422-3623 Cell kevin.beg...@lmco.com _______________________________________________________________________________ UNSUBSCRIBE or access ARSlist Archives at www.arslist.org Platinum Sponsor:rmisoluti...@verizon.net ARSlist: "Where the Answers Are"
