myeclipse性能优化.doc

性能优化 1 、关闭MyEclipse的自动validation windows perferences myeclipse validation 将Build下全部勾取消 如果你需要验证某个文件的时候，我们可以单独去验证它。方法是： 在需要验证的文件上( 右键 - MyEclipse - Run Validation 。 2、 启动优化，关闭不需要使用的模块 所以可以将一些不使用的模块禁止 加载启动。 Window Preferences General Startup andy Shutdown 在这里列出的是MyEclipse启动时加载的模块 我这里只让它加载tomcat6 勾选 MyEclipse EASIE Tomcat 6 。 WTP ：一个跟myeclipse差不多的东西，主要差别是 WTP 是免费的，如果使用myeclipse，这个可以取消 Mylyn：组队任务管理工具，类似于 CVS ，以任务为单位管理项目进度，没用到的可以取消 Derby：一种保存成 jar 形式的数据库，我没用到，取消 一大排以 MyEclipse EASIE 打头的启动项：myeclipse 支持的服务器，只选自己用的，其他取消， 比如我只选了 tomcat 。 3 、去掉MyEclipse的拼写检查（如果你觉的有用可以不去） 拼写检查会给我们带来不少的麻烦，我们的方法命名都会是单词的缩写，他也会提示有错， 所以最好去掉，没有多大的用处 Window perferences General Editors Text Editors Spelling 将Enable spell checking复选框的勾选去掉。 4 、修改MyEclipse编辑JSP页面时的编辑工具 Window perferences General Editors File Associations 在File types 中选择 *.jsp 在Associated editors 中将MyEclipse JSP Editor设置为默认。 还有XML文件的默认编辑器 5 、修改MyEclipse安装目录的myeclipse.ini文件，加大JVM的非堆内存 具体内容如下： -configuration configuration -vmargs -Xms256m -Xmx512m -XX:PermSize=128M -XX:MaxPermSize=256m -XX:ReservedCodeCacheSize=64m 6、使用JRockit作为Eclipse的Java VM Eclipse启动参数，指定eclipse启动时使用的jre E:MyEclipse8.0MyEclipse Blue Edition 8.0 GAmyeclipse-blue.exe -vm E:JRockitjrrt-3.1.2-1.6.0binjavaw.exe -vmargs -Xms256m -Xmx512m 在Eclipse里面，Window Preferences，然后选择Java Installed JREs添加JRockit，并设置为默认。 这样，就可以用JRockit来编译项目了。 7. 关闭自动更新 1.window-Perferences-General-Startup and Shutdown 勾掉 Automatic Updates Scheduler(自动更新调度程序) 2.window-Perferences-MyEclipse-Maven4MyEclipse 勾上 Enable Maven4MyEclipse featrures ;确定关闭窗口;该步骤是为了显示第3步中的Maven节点 3.window-Perferences-MyEclipse-Maven4MyEclipse Maven 勾掉 Download repository index updates on startupJVMTwo JVM options are often used to tune JVM heap size: -Xmx for maximum heap size, and -Xms for initial heap size. Here are some common mistakes I have seen when using them: Missing m, M, g or G at the end (they are case insensitive). For example,java -Xmx128 BigAppjava.lang.OutOfMemoryError: Java heap spaceThe correct command should be: java -Xmx128m BigApp. To be precise, -Xmx128 is a valid setting for very small apps, like HelloWorld. But in real life, I guess you really mean -Xmx128m Extra space in JVM options, or incorrectly use =. For example,java -Xmx 128m BigAppInvalid maximum heap size: -XmxCould not create the Java virtual machine.java -Xmx=512m HelloWorldInvalid maximum heap size: -Xmx=512mCould not create the Java virtual machine.The correct command should be java -Xmx128m BigApp, with no whitespace nor =. -X options are different than -Dkey=value system properties, where = is used. Only setting -Xms JVM option and its value is greater than the default maximum heap size, which is 64m. The default minimum heap size seems to be 0. For example,java -Xms128m BigAppError occurred during initialization of VMIncompatible initial and maximum heap sizes specifiedThe correct command should be java -Xms128m -Xmx128m BigApp. Its a good idea to set the minimum and maximum heap size to the same value. In any case, dont let the minimum heap size exceed the maximum heap size. Heap size is larger than your computers physical memory. For example,java -Xmx2g BigAppError occurred during initialization of VMCould not reserve enough space for object heapCould not create the Java virtual machine.The fix is to make it lower than the physical memory: java -Xmx1g BigApp Incorrectly use mb as the unit, where m or M should be used instead.java -Xms256mb -Xmx256mb BigAppInvalid initial heap size: -Xms256mbCould not create the Java virtual machine. The heap size is larger than JVM thinks you would ever need. For example,java -Xmx256g BigAppInvalid maximum heap size: -Xmx256gThe specified size exceeds the maximum representable size.Could not create the Java virtual machine.The fix is to lower it to a reasonable value: java -Xmx256m BigApp The value is not expressed in whole number. For example,java -Xmx0.9g BigAppInvalid maximum heap size: -Xmx0.9gCould not create the Java virtual machine.The correct command should be java -Xmx928m BigAppPS:How to set java heap size in Tomcat?Stop Tomcat server, set environment variable CATALINA_OPTS, and then restart Tomcat. Look at the file tomcat-install/bin/catalina.sh or catalina.bat for how this variable is used. For example,set CATALINA_OPTS=-Xms512m -Xmx512m (Windows)export CATALINA_OPTS=-Xms512m -Xmx512m (ksh/bash)setenv CATALINA_OPTS -Xms512m -Xmx512m (tcsh/csh)In catalina.bat or catallina.sh, you may have noticed CATALINA_OPTS, JAVA_OPTS, or both can be used to specify Tomcat JVM options. What is the difference between CATALINA_OPTS and JAVA_OPTS? The name CATALINA_OPTS is specific for Tomcat servlet container, whereas JAVA_OPTS may be used by other java applications (e.g., JBoss). Since environment variables are shared by all applications, we dont want Tomcat to inadvertently pick up the JVM options intended for other apps. I prefer to use CATALINA_OPTS.How to set java heap size in JBoss?Stop JBoss server, edit $JBOSS_HOME/bin/run.conf, and then restart JBoss server. You can change the line with JAVA_OPTS to something like:JAVA_OPTS=-server -Xms128m -Xmx128mHow to set java heap size in Eclipse?You have 2 options:1. Edit eclipse-home/eclipse.ini to be something like the following and restart Eclipse.-vmargs-Xms64m-Xmx256m2. Or, you can just run eclipse command with additional options at the very end. Anything after -vmargs will be treated as JVM options and passed directly to the JVM. JVM options specified in the command line this way will always override those in eclipse.ini. For example,eclipse -vmargs -Xms64m -Xmx256mHow to set java heap size in NetBeans?Exit NetBeans, edit the file netbeans-install/etc/netbeans.conf. For example,netbeans_default_options=-J-Xms512m -J-Xmx512m -J-XX:PermSize=32m -J-XX:MaxPermSize=128m -J-Xverify:noneHow to set java heap size in Apache Ant?Set environment variable ANT_OPTS. Look at the file $ANT_HOME/bin/ant or %ANT_HOME%binant.bat, for how this variable is used by Ant runtime.set ANT_OPTS=-Xms512m -Xmx512m (Windows)export ANT_OPTS=-Xms512m -Xmx512m (ksh/bash)setenv ANT_OPTS -Xms512m -Xmx512m (tcsh/csh)How to set java heap size in jEdit?jEdit is a java application, and basically you need to set minimum/maximum heap size JVM options when you run java command. jEdit by default runs with a default maximum heap size 64m. When you work on large files, you are likely to get these errors:java.lang.OutOfMemoryError: Java heap spaceat java.lang.String.concat(String.java:2001)at org.gjt.sp.jedit.buffer.UndoManager.contentInserted(UndoManager.java:160)at org.gjt.sp.jedit.Buffer.insert(Buffer.java:1139)at org.gjt.sp.jedit.textarea.JEditTextArea.setSelectedText(JEditTextArea.java:2052)at org.gjt.sp.jedit.textarea.JEditTextArea.setSelectedText(JEditTextArea.java:2028)at org.gjt.sp.jedit.Registers.paste(Registers.java:263)How to fix it? If you click a desktop icon, or Start menu item to start jEdit: right-click the icon or menu item, view its property, and you can see its target is something like:C:jdk6binjavaw.exe -jar C:jeditjedit.jarYou can change that line to:C:jdk6binjavaw.exe -Xmx128m -Xms128m -jar C:jeditjedit.jarIf you run a script to start jEdit: just add these JVM options to the java line inside the script file:java -Xmx128m -Xms128m -jar jedit.jarIf you start jEdit by running java command: just add these JVM options to your java command:java -Xmx128m -Xms128m -jar jedit.jarNote that when you run java with -jar option, anything after -jar jar-file will be treated as application arguments. So you should always put JVM options before -jar. Otherwise, you will get error:C:jeditjava -jar jedit.jar -Xmx128mUnknown option: -Xmx128mUsage: jedit How to set java heap size in JavaEE SDK/J2EE SDK/Glassfish/Sun Java System Application S