java大型网站系统调优

架构核心：

 jboss4_05 + apache2.059+ mod_jk (1.4) + oracle 9i。 其中jboss采用自带的连接池，而非dbcp。

调优分为多个层面

1 apache 采用worker PMP模型

  httpd.conf

  Timeout 50
KeepAlive On
MaxKeepAliveRequests 30
KeepAliveTimeout 25

StartServers         2
ServerLimit          500
MaxClients           1500
MinSpareThreads      50
MaxSpareThreads      1500
ThreadsPerChild      50
MaxRequestsPerChild  10000

适当放大ServerLimit  ,MaxClients . MaxClients有效取值范围<=ServerLimit  

2 jboss server.xml

    <Connector port="8009" address="${jboss.bind.address}"
         emptySessionPath="true" enableLookups="false" redirectPort="8443"
         maxThreads="250" maxProcessors="350" minSpareThreads="30" backlog="400"
         connectionTimeout="600000" protocol="AJP/1.3"/>

 3 jvm参数

 -server -Xms1536m -Xmx1536m -XX:NewSize=256m -XX:MaxNewSize=256m -XX:PermSize=96m -XX:MaxPermSize=96m -XX:+UseConcMarkSweepGC -XX:+CMSPermGenSweepingEnabled -XX:+CMSClassUnloadingEnabled -Djboss.platform.mbeanserver

 4 workers.properties

worker.localnode.connection_pool_size=50
worker.localnode.connection_pool_minsize=25
worker.localnode.connection_pool_timeout=600

# Load-balancing behaviour

  5 oracle-ds.xml

    <connection-property name="SetBigStringTryClob">true</connection-property>
    <connection-property name="defaultRowPrefetch">50</connection-property>
    <driver-class>com.alibaba.jdbc.AlibabaDriver</driver-class>

    <min-pool-size>2</min-pool-size>
    <max-pool-size>125</max-pool-size>
    <blocking-timeout-millis>5000</blocking-timeout-millis>
    <idle-timeout-minutes>1</idle-timeout-minutes>
    <max-idle-timeout>3</max-idle-timeout>
    <prepared-statement-cache-size>50</prepared-statement-cache-size>
    <metadata><type-mapping>Oracle9i</type-mapping></metadata>
    <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter</exception-sorter-class-name>

  6 oracle 放大open cursor以及process数目。当然SQL tuning是性能调整重中之中。