weblogic 性能相關的幾個配置

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

• 設置Initial Capacity等于Maximum Capacity

• 設置Statement cache（注意，對于每個打開的statement，DBMS都會維護一個cursor，這個值設置過大會導致 java.sql.SQLException: ORA-01000: maximum open cursors exceeded類似的錯誤。當然，你要清楚，statement cache的大小是指每個連接能cache的statement數，例如你設置connection pool size = 100 ,設置Statement Cache = 10，那系統最大維持的cursor為100*10）

Network connection

• Enable Native IO （注意，不是java的NIO，采用Java muxer方式處理連接，對于大并發的系統影響巨大，java需要為每個連接請求起一個線程來處理）

• 修改Accept Backlog，當應用服務器出現拒絕連接的時候

啟動腳本

• 使用productmode啟動weblogic

• 設置-xms等于-xmx

• 盡量使用jrockit

work manager

• 從9版本以后，weblogic用work manager取代了thread queue，默認情況下，weblogic有一個default work manager，采用fair share方式平均共享線程

• 一般你不需要自己創建work manager，除非你有如下需求：

  • 你的應用有優先級

  • 你需要滿足SLA定義的響應時間

  • 需要指定最小線程約束來避免服務器死鎖

posted on 2007-10-19 16:22 tacy lee 閱讀(1775) 評論(0)  編輯  收藏 所屬分類: 性能相關