JVM 参数

JAVA_OPTS=
"-server
-Xms2048m                 
-Xmx2048m
-XX:PermSize=256m
-XX:MaxPermSize=256m
-XX:NewSize=512m
-XX:MaxNewSize=512m
-Xss256k -XX:SurvivorRatio=6
- XX:+DisableExplicitGC 
-XX:+UseConcMarkSweepGC 
-XX:+UseParNewGC 

-XX:+CMSParallelRemarkEnabled
-XX:+UseCMSCompactAtFullCollection
-XX:LargePageSizeInBytes=128m
-XX:+UseFastAccessorMethods
-XX:+UseCMSInitiatingOccupancyOnly
-XX:CMSInitiatingOccupancyFraction=65
-XX:-UseGCOverheadLimit
-XX:+HeapDumpOnOutOfMemoryError
-Djava.awt.headless=true" 

jetty.sh 中
JAVA_OPTIONS+=("-Dfile.encoding=UTF-8")
JAVA_OPTIONS+="-server -Xms4096m -Xmx4096m -XX:PermSize=256m -XX:MaxPermSize=256m -XX:+UseConcMarkSweepGC -XX:+CMSClassUnloadingEnabled"

具体参数的详细解释请参考下午
http://blog.csdn.net/lifetragedy/article/details/7708724

Web 应用 1G内存
-server
-Xms1024m
-Xmx1024m
-XX:NewSize384m
-XX:MaxNewSize384m
-XX:Permsize=64m
-XX:MaxPermSize=64m
-XX:+UseConcMarkSweepGC
-XX:+CMSClassUnloadingEnabled
-XX:+MaxTenuringThreshold=5   回收线程线按机器核数来，机器核数-1