1.参考：
http://blog.csdn.net/fox009/article/details/5633007
http://hi.baidu.com/like_dark/blog/item/19c1948b3292b0799f2fb468.html
http://anyeeye.iteye.com/blog/444624
Tomcat6性能调优 出现java.lang.OutOfMemoryError: PermGen space
http://www.mkyong.com/tomcat/tomcat-javalangoutofmemoryerror-permgen-space/
2.报错：
Exception in thread "DispatcherThread"
java.lang.OutOfMemoryError: PermGen space
Exception in thread
"ContainerBackgroundProcessor[StandardEngine[Catalina]]"
java.lang.OutOfMemoryError: PermGen space
Exception in thread
"State Saver"
java.lang.OutOfMemoryError: PermGen space
Exception in thread
"AWT-Windows" java.lang.OutOfMemoryError: OutOfMemoryError
3.原因：
PermGen space的全称是Permanent Generation space,是指内存的永久保存区域,这块内存主要是被JVM存放Class和Meta信息的,Class在被Loader时就会被放到PermGen space中,它和存放类实例(Instance)的Heap区域不同,GC(Garbage Collection)不会在主程序运行期对PermGen space进行清理，所以如果你的应用中有很多CLASS的话,就很可能出现PermGen space错误,这种错误常见在web服务器对JSP进行pre compile的时候。如果你的WEB APP下都用了大量的第三方jar, 其大小超过了jvm默认的大小(4M)那么就会产生此错误信息了。
4.解决方法1：
手动设置MaxPermSize大小，如果是linux系统，修改TOMCAT_HOME/bin/catalina.sh，如果是windows系统，修改TOMCAT_HOME/bin/catalina.bat，
在“echo "Using CATALINA_BASE: $CATALINA_BASE"”上面加入以下行：
JAVA_OPTS="-server -XX:PermSize=64M -XX:MaxPermSize=128m
建议：将相同的第三方jar文件移置到tomcat/shared/lib目录下，这样可以达到减少jar 文档重复占用内存的目的。
5.解决方法2
修改eclipse.ini文件，修改如下：
-
vmargs
-Dosgi.requiredJavaVersion=1.5
-
Xms128m
-
Xmx512m
-XX:PermSize=
64M
-XX:MaxPermSize=128M
如果还报错，可以考虑如下修改
-
vmargs
-Dosgi.requiredJavaVersion=1.5
-
Xms512m
-
Xmx1024m
-XX:PermSize=
256M
-XX:MaxPermSize=512M
报错：
2011-11-21 21:10:46
org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc
严重: The web application [
/
Application] registered the JDBC driver [com.mysql.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
2011-11-21 21:10:46
org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [
/
Application] appears to have started a thread named [MySQL Statement Cancellation Timer] but has failed to stop it. This is very likely to create a memory leak.
2011-11-21 21:10:46
org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [
/Application] appears to have started a thread named [AWT-
Windows] but has failed to stop it. This is very likely to create a memory leak.
2011-11-21 21:10:46
org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [
/Application] appears to have started a thread named [Thread-14
] but has failed to stop it. This is very likely to create a memory leak.
2011-11-21 21:10:46
org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap
严重: The web application [
/Application] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1
@3661eeb]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.
2011-11-21 21:10:50
org.apache.catalina.core.ApplicationContext log
信息: Initializing Spring FrameworkServlet
'Dispatcher'
修改catalina.bat
添加
JAVA_OPTS="-Djava.awt.headless=true -Dfile.encoding=UTF-8
-server -Xms1536m -
Xmx1536m
-XX:NewSize=256m -XX:MaxNewSize=256m -XX:PermSize=
256m
-XX:MaxPermSize=256m -XX:+DisableExplicitGC"
样例
# JSSE_HOME (Optional) May point at your Java Secure Sockets Extension
# (JSSE) installation, whose JAR files will be added to the
# system
class
path used to start Tomcat.
#
# CATALINA_PID (Optional) Path of the file which should contains the pid
# of catalina startup java process, when start (fork) is used
#
# $Id: catalina.sh
609438 2008-01-06 22:14
:28Z markt $
#
-----------------------------------------------------------------------------
JAVA_OPTS
="-Djava.awt.headless=true -Dfile.encoding=UTF-8 -server -Xms1536m
-Xmx1536m -XX:NewSize=256m -XX:MaxNewSize=256m -XX:PermSize=
256m
-XX:MaxPermSize=256m -XX:+DisableExplicitGC
"
# OS specific support. $var _must_ be set to either
true
or
false
.
cygwin
=
false
os400
=
false
darwin
=
false
case
"`uname`"
in
CYGWIN
*) cygwin=
true
;;
OS400
*) os400=
true
;;
Darwin
*) darwin=
true
;;
esac
# resolve links
- $0
may be a softlink
PRG
="$0"
具体参数根据自己机器情况而定
JAVA_OPTS="-Djava.awt.headless=true -Dfile.encoding=UTF-8 -server -Xms512m
-Xmx512m -XX:NewSize=256m -XX:MaxNewSize=256m -XX:PermSize=
256m
-XX:MaxPermSize=256m -XX:+DisableExplicitGC"
