MULTI-THREADED SERVER ARCHITECTUE

Uses of Multithreaded server

1.     Reduce the number of processes running against instance.
2.     Increase the number of possible users.
3.     Achieve load balancing(Server start and terminate automatically)
4.     Reduce the number of idle server processes
5.     Reduce memory usage and system overhead.


Connecting in MULTI-THREADED SERVER ARCHITECTUE.

The listener processes waits for connection requests from user processes, then determines if each user processes can use a shared server process.
When the user can use shared server, the listener gives the user process the address of dispatcher process.
When the user process requests for dedicated server, the listener creates dedicated server process ad connects user process to it.



PROCESSING A REQUEST

A user send a request to its dispatcher.
The dispatcher places the request into the request queue in the SGA.
A shared server picks up the request from the request queue and processes the  request.
The shared server places the response on the calling dispatchers response queue
The dispatcher returns the response to the user.


Steps to configure Multi-threaded Server.

1.   Configure and start the listener process.
2.     Specify the dispatcher service name
3.     Specify the initial number of dispatchers
4.     Specify the maximum number of dispatchers
5.     Specify the initial number of shared servers
6.     specify the maximum number of shared servers


In the parameter file following  parameter are to be set.
MTS_LISTENER_ADDRESS    :Address of listener process
“(address=(protocol=tcp)(host=erseq5)   (PORT=7000))”
MTS_SERVICE            ;Name of the service
MTS_DISPATCHERS        :Initial number of dispatcher process
MTS_MAX_DISPATCHERS    :Maximum number of dispatcher process
MTS_SERVERS            :Initial number of shared servers
MTS_MAX_SERVERS        :Maximum number of shared servers.



Steps to start listener process .

1)Login as ORACLE7 with the password larry
2)Go to $ORACLE_HOME/rdbms/admin  dir
3)$lsnrctl  start     (this command will start the listener process, it is advised to start the listener process before the starting database).

On the client end connect string has to be specified in the file tnsnames.ora

Colin = (Description = (Address=(Protocol=TCP) (Host=erseq5) (PORT=7000) (CONNECT_DATA=(SID=prod)))
$sqlplus  scott/tiger@colin