I have set the heap size of tomcat 7 by adding the following line in catalina.sh
export CATALINA_OPTS="-Xms512m -Xmx1024m"
then stopped and started the tomcat. but when tried to get the heap size using the command jmap -heap , i can notice that the memory doesn't change:
Heap Configuration:
MinHeapFreeRatio = 40
MaxHeapFreeRatio = 70
MaxHeapSize = 526385152 (502.0MB)
NewSize = 1048576 (1.0MB)
MaxNewSize = 4294901760 (4095.9375MB)
OldSize = 4194304 (4.0MB)
NewRatio = 2
SurvivorRatio = 8
PermSize = 16777216 (16.0MB)
MaxPermSize = 67108864 (64.0MB)
Heap Usage:
PS Young Generation
Eden Space:
capacity = 99352576 (94.75MB)
used = 9643144 (9.196418762207031MB)
free = 89709432 (85.55358123779297MB)
9.705982862487632% used
From Space:
capacity = 4063232 (3.875MB)
used = 0 (开发者_如何学JAVA0.0MB)
free = 4063232 (3.875MB)
0.0% used
To Space:
capacity = 5177344 (4.9375MB)
used = 0 (0.0MB)
free = 5177344 (4.9375MB)
0.0% used
PS Old Generation
capacity = 37748736 (36.0MB)
used = 21889008 (20.874984741210938MB)
free = 15859728 (15.125015258789062MB)
57.98606872558594% used
PS Perm Generation
capacity = 60948480 (58.125MB)
used = 31496008 (30.03693389892578MB)
free = 29452472 (28.08806610107422MB)
51.67644541750672% used
please advise.
sudo vi /etc/default/tomcat7
Find the line that begins JAVA_OPTS="-Djava.awt.headless=true
and change the piddly -Xmx128m
to -Xms512m -Xmx1024m
If you have more than one core...-XX:+UseConcMarkSweepGC
is probably what you want.
Do not change catalina.sh
!! This file is not supposed to be changed by user. Tomcat updates may override it. Instead create a file called "setenv.sh" in your "$CATALINA_BASE/bin" (same folder as catalina.sh
). Set all your environment variables there.
setenv.sh
is an optional file. If it exists it gets imported by catalina.sh
. And the name suggests what you put there. This is a proper place to initialize your $CATALINA_OPTS, $JAVA_OPTS, etc.
P.S. Generally speaking you should avoid tweaking files that can can change with package/distribution update provided and alternative configuration approach exists. In this case files like catalina.sh
, /etc/tomcat7/tomcat7.conf
, /etc/init.d/tomcatX
etc can be updated silently and you won't even notice that your configuration changes are rolled back.
how about editing etc/default/tomcat7
# You may pass JVM startup parameters to Java here. If unset, the default
# options will be: -Djava.awt.headless=true -Xmx128m -XX:+UseConcMarkSweepGC
#
# Use "-XX:+UseConcMarkSweepGC" to enable the CMS garbage collector (improved
# response time). If you use that option and you run Tomcat on a machine with
# exactly one CPU chip that contains one or two cores, you should also add
# the "-XX:+CMSIncrementalMode" option.
JAVA_OPTS="-Djava.awt.headless=true -Xmx1280m -XX:+UseConcMarkSweepGC"
Set additionally export JAVA_OPTS="-Dcom.sun.management.jmxremote"
and use JConsole to inspect the tomcats memory consumption.
Goto your catalina.sh
Add these line at the beginning
JAVA_OPTS="-Djava.awt.headless=true -Dfile.encoding=UTF-8
-server -Xms512m -Xmx1024m
-XX:NewSize=256m -XX:MaxNewSize=256m -XX:PermSize=256m
-XX:MaxPermSize=256m -XX:+DisableExplicitGC"
Then start your tomcat using startup.sh
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