Tomcat's Max Thread problem

[sihan]

Hi,

I am using tomcat as my server and there is about 130 servlet in my web
application.
I want to increase the number of concurrent users in my server. Currently it
supports about 200 concurrent requests (tested by JMETER).
I tried tuning the number of threads (maxThreads) in tomcat's thread pool in
server.xml. But I found no change. It still can't serve more than 200
concurrent requests.  I am not an expert in server side technologies. 
Please help me in this regards.


This is my server environment and tomcat's server.xml:

============================================================================
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Database Server: MySQL version 5.0.41
Java Version: 1.6_05
Tomcat Server: Version 6.0.16 (Binary Distribution)
Server configuration: Intel Core 2 Duo 1.86 GHZ; 2 GB of Memory; Windows XP
Service Pack 2
Load Test Tool: Jakarta JMeter

Server.xml:
<?xml version='1.0' encoding='utf-8'?>
<Server port="8006" shutdown="SHUTDOWN">
  <Listener className="org.apache.catalina.core.AprLifecycleListener"
SSLEngine="on" />
  <Listener className="org.apache.catalina.core.JasperListener" />
  <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener"
/>
  <Listener
className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
  <GlobalNamingResources>
    <Resource name="UserDatabase" auth="Container"
              type="org.apache.catalina.UserDatabase"
              description="User database that can be updated and saved"
              factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
              pathname="conf/tomcat-users.xml" />
  </GlobalNamingResources>   
   <Service name="Catalina">     
    <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" 
        maxThreads="300" minSpareThreads="20" maxSpareThreads="30"
acceptCount="350" />    
   <Connector port="8086" protocol="HTTP/1.1" 
               connectionTimeout="20000" 
               redirectPort="8443" />      
    <Connector port="8009" protocol="AJP/1.3" redirectPort="8443" />
    <Engine name="Catalina" defaultHost="localhost">
      <Realm className="org.apache.catalina.realm.UserDatabaseRealm"
             resourceName="UserDatabase"/>
      <Host name="localhost"  appBase="webapps"
            unpackWARs="true" autoDeploy="true"
            xmlValidation="false" xmlNamespaceAware="false">
      </Host>
    </Engine>
  </Service>
</Server>
============================================================================
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Regards,
Foyez