Hi Tobias, I use this:
JAVA_OPTS="$JAVA_OPTS -d64 -Xms512m -Xmx4096m" but can not find -d64 in the command line passed to java, looks like -d64 is not needed. in the tomcat manager, it does show JVM memory as: Free memory: 325.24 MB Total memory: 490.68 MB Max memory: 3640.93 MB Am I really in the 64bit mode JVM? Thanks Tobias Crefeld-2 wrote: > > Am Mon, 9 Aug 2010 04:52:55 -0700 (PDT) > schrieb Angelo Chen <angelochen...@yahoo.com.hk>: > >> >> the standard tomcat(apache-tomcat-6.0.20.tar.gz) is running in a 64 >> bit version of Centos. so can my app use memory bigger than 4G? I > > Which JVM-version does your Tomcat use? IIRC there are different > defaults for different versions of CentOS. Maybe > "yum list installed |grep ^java" > or > "yum list installed |grep ^jdk" > helps. > > I would download last JDK for Linux/x64 at > http://java.sun.com/javase/downloads/index.jsp, install it and set the > correct path, for example: "JAVA_HOME=/usr/jdk/latest;export JAVA_HOME" > before starting Tomcat. > > Maybe defaults of JVM have changed but AFAIK you have to set some > additional JAVA_OPTS-parameters to use 64bit and more RAM. We are using > a scriptlet like the following on our larger machines as part of the > catalina.sh or start-stop-wrapper for catalina.sh: > > ------------------------schnipp------------------------ > JAVA_OPTS="$JAVA_OPTS "-server > JAVA_OPTS="$JAVA_OPTS "-d64 > # Speicherlimit nur bei Aufruf von run, debug oder start auf 3 GB oder > mehr hochsetzen > case "$1" in > start|run|debug) > # Fuer 32-Bit-Betrieb die naechsten beiden Zeilen auf 3072k aendern > JAVA_OPTS="$JAVA_OPTS "-Xms6000m > JAVA_OPTS="$JAVA_OPTS "-Xmx11000m > ;; > stop) > JAVA_OPTS="$JAVA_OPTS "-Xms600m > JAVA_OPTS="$JAVA_OPTS "-Xmx600m > ;; > esac > ------------------------schnipp------------------------ > > > >> believe the 2G is the limit for 32 bit version of Linux. > > 3GB is a possible limit for 32bit. > > > Regards, > Tobias. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > > > -- View this message in context: http://old.nabble.com/64-bit-version-for-linux-tp29386189p29396387.html Sent from the Tomcat - User mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org