On Tue, Apr 12, 2011 at 14:26, André Warnier <a...@ice-sa.com> wrote: > Francis GALIEGUE wrote: >> >> On Tue, Apr 12, 2011 at 12:20, André Warnier <a...@ice-sa.com> wrote: >> [...] >>> >>> Considering all the above, which would be the easiest/quickest way of >>> starting to figure out what this tomcat is doing, and where the >>> system/application bottleneck might be ? >>> >> >> We have the following tools, all very easy to setup and run: >> >> * SNMP monitoring of the JVM (allows to see the amount of memory >> consumed, the number of threads, and others - the MIB is well >> defined); >> * a shell script sending the results of a kill -3 on the JVM (a thread >> dump); >> * a script which triggers when a java.lang.OutOfMemoryError is thrown. >> >> If you are interested in any of it, I can tell you how we do it. >> >> And, considering that your server has 12 GB RAM, you could indeed do >> with a little more heap space! >> > > Thanks. I think I'll accept your offer of details. > > I don't think that OOM is a problem, but the first 2 would be a good start. > > About SNMP monitoring : I already have a "munin agent" installed on that > system, and a munin server collecting stuff like overall cpu and memory > usage. > To your knowledge, does there exist a way to collect this JVM SNMP > information via a munin plugin ? >
I don't use Munin, I use cacti, but if Munin can collect SNMP information then it's only a matter of having Munin fetch the appropriate OIDs. More details in a separate mail. > > About the script doing a kill -3 : where does the thread dump go, when you > do that ? and how does the script know which PID is Tomcat ? > Mine does since the environment fetches the PID file and sends the signal to that process. It sends output to either stdout or stderr, I don't know. Script attached. Read the comments carefully, it is somewhat a hack (could be improved by detecting, say, if the output went to stderr). > On that system, the tomcat processes look like this : > > # ps -ef | grep java > root 20997 1 0 12:18 ? 00:00:00 /usr/bin/jsvc -user tomcat55 > -cp > /usr/share/java/commons-daemon.jar:/usr/share/tomcat5.5/bin/bootstrap.jar > -outfile SYSLOG -errfile SYSLOG -pidfile /var/run/tomcat5.5.pid > -Djava.awt.headless=true -Xms128M -Xmx128M > -Djava.endorsed.dirs=/usr/share/tomcat5.5/common/endorsed > -Dcatalina.base=/var/lib/tomcat5.5 -Dcatalina.home=/usr/share/tomcat5.5 > -Djava.io.tmpdir=/var/lib/tomcat5.5/temp > -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager > -Djava.util.logging.config.file=/var/lib/tomcat5.5/conf/logging.properties > org.apache.catalina.startup.Bootstrap > root 20998 20997 0 12:18 ? 00:00:00 /usr/bin/jsvc -user tomcat55 > -cp > /usr/share/java/commons-daemon.jar:/usr/share/tomcat5.5/bin/bootstrap.jar > -outfile SYSLOG -errfile SYSLOG -pidfile /var/run/tomcat5.5.pid > -Djava.awt.headless=true -Xms128M -Xmx128M > -Djava.endorsed.dirs=/usr/share/tomcat5.5/common/endorsed > -Dcatalina.base=/var/lib/tomcat5.5 -Dcatalina.home=/usr/share/tomcat5.5 > -Djava.io.tmpdir=/var/lib/tomcat5.5/temp > -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager > -Djava.util.logging.config.file=/var/lib/tomcat5.5/conf/logging.properties > org.apache.catalina.startup.Bootstrap > tomcat55 20999 20997 0 12:18 ? 00:00:04 /usr/bin/jsvc -user tomcat55 > -cp > /usr/share/java/commons-daemon.jar:/usr/share/tomcat5.5/bin/bootstrap.jar > -outfile SYSLOG -errfile SYSLOG -pidfile /var/run/tomcat5.5.pid > -Djava.awt.headless=true -Xms128M -Xmx128M > -Djava.endorsed.dirs=/usr/share/tomcat5.5/common/endorsed > -Dcatalina.base=/var/lib/tomcat5.5 -Dcatalina.home=/usr/share/tomcat5.5 > -Djava.io.tmpdir=/var/lib/tomcat5.5/temp > -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager > -Djava.util.logging.config.file=/var/lib/tomcat5.5/conf/logging.properties > org.apache.catalina.startup.Bootstrap > vogon2:~# > > So there are 3 Tomcat-related processes, all running under jsvc. I am not > quite sure which one does what. > Wild guess: it's the one in the PID file that matters (-pidfile /xxxxxxx). It should be a variable in the Tomcat base configuration file. -- Francis Galiegue ONE2TEAM Ingénieur système Mob : +33 (0) 683 877 875 Tel : +33 (0) 178 945 552 f...@one2team.com 40 avenue Raymond Poincaré 75116 Paris
--------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
