Shared server in Oracle

Parameters related to shared server
SHARED_SERVERS: Specifies the initial number of shared servers to start and the minimum number of shared servers to keep. This is the only required parameter for using shared servers.

MAX_SHARED_SERVERS: Specifies the maximum number of shared servers that can run simultaneously.

SHARED_SERVER_SESSIONS: Specifies the total number of shared server user sessions that can run simultaneously. Setting this parameter enables you to reserve user sessions for dedicated servers.

DISPATCHERS: Configures dispatcher processes in the shared server architecture.

MAX_DISPATCHERS: Specifies the maximum number of dispatcher processes that can run simultaneously. this parameter can be ignored for now. it will only be useful in a future release when the number of dispatchers is auto-tuned according to the number of concurrent connections.

CIRCUITS: Specifies the total number of virtual circuits that are available for inbound and outbound network sessions

Use shared server
Alter system set shared_servers = 5;

Do not use shared server
Alter system set shared_server = 0;
Alter system set dispatchers = '';

You can still use Dedicated mode when using shared servers. You only need to add servers = dedicated to tnsnames. ora. shared server is used when shared is used.
If not, check the dispatchers parameter.
Typical examples are DISPATCHERS = "(PROTOCOL = TCP) (DISPATCHERS = 2 )"
Three related view V $ queue v $ dispatcher v $ DISPATCHER_RATE

View dispatcher
Select name, network from v $ DISPATCHER;
Shutdown dispatcher
Alter system shutdown immediate 'd002 ';

For more information about Oracle, see Oracle topics page http://www.bkjia.com/topicnews.aspx? Tid = 12