weblogic 性能相关的几个配置(转 作者：tacy lee)

weblogic.xml
<container-descriptor>

servlet-reload-check-secs

The <servlet-reload-check-secs> element defines whether a WebLogic Server will check to see if a servlet has been modified, and if it has been modified, reloads it.

The value -1 means never check the servlets. This is the default value in a production environment.

The value 0 means always check the servlets.

The value 1 means check the servlets every second. This is the default value in a development environment.

A value specified in the console will always take precedence over a manually specified value.

resource-reload-check-secs

The <resource-reload-check-secs> element is used to perform metadata caching for cached resources that are found in the resource path in the Web application scope. This parameter identifies how often WebLogic Server checks whether a resource has been modified and if so, it reloads it.

The value -1 means metadata is cached but never checked against the disk for changes. In a production environment, this value is recommended for better performance.

The value 0 indicates not to do any metadata caching. Customers who keep changing their files must set this parameter to a value greater than or equal to 0.

The value 1 means reload every second. This is the default value in a development environment.

Values specified for this parameter using the Admin Console are given precedence.

native-io-enabled

To use native I/O while serving static files with weblogic.servlet.FileServlet, which is implicitly registered as the default servlet, set native-io-enabled to true. (The default value is false.) native-io-enabled element applies only on Windows.

<jsp-descriptor>

page-check-seconds

Sets the interval, in seconds, at which WebLogic Server checks to see if JSP files have changed and need recompiling. Dependencies are also checked and recursively reloaded if changed.

The value -1 means never check the pages. This is the default value in a production environment.

The value 0 means always check the pages.

The value 1 means check the pages every second. This is the default value in a development environment.

In a production environment where changes to a JSP are rare, consider changing the value of pageCheckSeconds to 60 or greater, according to your tuning requirements.

JDBC
设置Initial Capacity等于Maximum Capacity

设置Statement cache（注意，对于每个打开的statement，DBMS都会维护一个cursor，这个值设置过大会导致 java.sql.SQLException: ORA-01000: maximum open cursors exceeded类似的错误。当然，你要清楚，statement cache的大小是指每个连接能cache的statement数，例如你设置connection pool size = 100 ,设置Statement Cache = 10，那系统最大维持的cursor为100*10）

Network connection
Enable Native IO （注意，不是java的NIO，采用Java muxer方式处理连接，对于大并发的系统影响巨大，java需要为每个连接请求起一个线程来处理）

修改Accept Backlog，当应用服务器出现拒绝连接的时候

启动脚本
使用productmode启动weblogic

设置-xms等于-xmx

尽量使用jrockit

work manager
从9版本以后，weblogic用work manager取代了thread queue，默认情况下，weblogic有一个default work manager，采用fair share方式平均共享线程

一般你不需要自己创建work manager，除非你有如下需求：

你的应用有优先级

你需要满足SLA定义的响应时间

需要指定最小线程约束来避免服务器死锁