DISPATCHERS

Parameter type	String
Syntax	DISPATCHERS = 'dispatch_clause'
	dispatch_clause::= (PROTOCOL = protocol) | (ADDRESS = address) | (DESCRIPTION = description ) [options_clause]
	options_clause::= (DISPATCHERS = integer | SESSIONS = integer | CONNECTIONS = integer | TICKS = seconds | POOL = {1 | ON | YES | TRUE | BOTH | ({IN | OUT} = ticks) | 0 | OFF | NO | FALSE | ticks} | MULTIPLEX = {1 | ON | YES | TRUE | 0 | OFF | NO | FALSE | BOTH | IN | OUT} | LISTENER = tnsname | SERVICE = service | INDEX = integer)
Default value	There is no default value.
Parameter class	Dynamic: ALTER SYSTEM

DISPATCHERS configures dispatcher processes in the shared server architecture. The parsing software supports a name-value syntax to enable the specification of attributes in a position-independent case-insensitive manner. For example:

DISPATCHERS = "(PROTOCOL=TCP)(DISPATCHERS=3)"

Specify only one of the following attributes: PROTOCOL, ADDRESS, or DESCRIPTION. If you specify either ADDRESS or DESCRIPTION, then you can specify additional network attributes. Doing so supports multi-homed hosts.

dispatch_clause

• PROTOCOL (PRO or PROT)

  The network protocol for which the dispatcher generates a listening endpoint.

• ADDRESS (ADD or ADDR)

  The network protocol address of the endpoint on which the dispatchers listen.

• DESCRIPTION (DES or DESC)

  The network description of the endpoint on which the dispatchers listen, including the protocol address.

options_clause

• DISPATCHERS (DIS or DISP)

  The initial number of dispatchers to start. The default is 1.

• SESSIONS (SES or SESS)

  The maximum number of network sessions to allow for each dispatcher. The default is operating system-specific. Most operating systems have a default of 16 KB.

• CONNECTIONS (CON or CONN)

  The maximum number of network connections to allow for each dispatcher. The default is operating system-specific.

• TICKS (TIC or TICK)

  The length of a network tick in seconds. The default is 1 second.

• POOL (POO)

  Enables Connection Pooling.

  • An integer indicates that Connection Pooling is enabled for both incoming and outgoing network connections. The number specified is the timeout in ticks for both incoming and outgoing network connections.
  • ON, YES, TRUE, and BOTH indicate that Connection Pooling is enabled for both incoming and outgoing network connections. A default timeout of 10 ticks is used for both incoming and outgoing network connections.
  • IN indicates that Connection Pooling is enabled for incoming network connections and the default timeout of 10 ticks is used for incoming network connections.
  • OUT indicates that Connection Pooling is enabled for outgoing network connections and the default timeout of 10 ticks is used for outgoing network connections.
  • NO, OFF, and FALSE indicate that Connection Pooling is disabled for both incoming and outgoing network connections. This is the default.

POOL can also be assigned a name-value string such as: "(IN=10)", "(OUT=20)", or "(IN=10)(OUT=20)". In such cases:

• MULTIPLEX (MUL or MULT)

  Enables the Oracle Connection Manager session multiplexing feature.

  • The values 1, ON, YES, TRUE, and BOTH indicate that Network Session Multiplex is enabled for both incoming and outgoing network connections.
  • The value IN indicates that Network Session Multiplex is enabled for incoming network connections.
  • The value OUT indicates that Network Session Multiplexing is enabled for outgoing network connections.
  • The values 0, NO, OFF, and FALSE indicate that Network Session Multiplexing is disabled for both incoming and outgoing network connections. This is the default.
• LISTENER (LIS, LIST)

  Specifies the network name of an address or address list of the Oracle Net listeners with which the dispatchers will register.

  The LISTENER attribute facilitates administration of multi-homed hosts. This attribute specifies the appropriate listeners with which the dispatchers will register. The LISTENER attribute takes precedence over the LOCAL_LISTENER and REMOTE_LISTENER parameters. See "LOCAL_LISTENER" and "REMOTE_LISTENER".

• SERVICE (SER, SERV)

  The service names the dispatchers register with the listeners.

• INDEX

  Use this parameter in an ALTER SYSTEM SET DISPATCHERS statement to indicate which dispatcher you want to modify. (If you specify INDEX in the initialization parameter file, Oracle ignores it.) In an ALTER SYSTEM statement, INDEX specifies the order in which the parameter's values were initialized. The value ranges from 0 (for the first dispatcher process) to one less than the total number of dispatchers you define.

  For example, if you specify 3 dispatchers in the initialization parameter file, you would modify the third dispatcher by specifying INDEX=2 in the ALTER SYSTEM statement. You could also add an additional dispatcher in the ALTER SYSTEM statement by specifying INDEX=3.

  See Also: Oracle9i Net Services Administrator's Guide for more information on setting this parameter