How can I make a large number connections using ActiveMQ? (more than 1k conns)

[William]

Dear team,

        We encounter a bottleneck that we can’t establish more than 1k 
connections on a single ActiveMQ server.
Our purpose is that we gonna sending messages to 1 million clients using 
ActiveMQ cluster(by network broker cluster mode).
So I wonder how many connections MQ support for single server?

        0, Environment
                Server:
                CentOS Linux 6, 64bit, Java7
                ActiveMQ 5.9
                Client:
                Mac OS 10.9/Windows 7
                Java7

        1, I modify configuration on server side as below:

<transportConnector name="openwire" 
uri="tcp://0.0.0.0:61616?transport.maximumConnections=10000&amp;wireFormat.maxFrameSize=10485760000”/>

        2, modify linux open files number
                add ‘* - no file 65536’ to /etc/security/limits.conf
                add ‘fs.file-max=65536’ to /etc/sysctl.conf
        3, in client code, I use ActiveMQConnectionFactory to create connection

                connectionFactory = new ActiveMQConnectionFactory( 
                         ActiveMQConnection.DEFAULT_USER, 
                         ActiveMQConnection.DEFAULT_PASSWORD, 
                         
"tcp://192.168.1.230:61616?wireFormat.maxInactivityDuration=0&wireFormat.maxInactivityDurationInitalDelay=60000&soTimeout=60000");
                     
((ActiveMQConnectionFactory)connectionFactory).setMaxThreadPoolSize(5000);

        but unlucky, the program halt on establishing the 968th connection 
every time.
        We never establish more than 1000 connections.

        So Is there having any way to achieve my requirement? Or Is there 
having some places I can take effort or work on? 

        Thanks in advance.


        Best Regards
        William
        2015/1/28