126 DBMS_PROCESS
The DBMS_PROCESS
package provides an interface to manage the prespawned servers.
This chapter contains the following topics:
126.1 DBMS_PROCESS Overview
By default, Oracle Database can prespawn foreground processes to improve the performance of client connections.
A prespawned process refers to a process that has been spawned but does not have a session yet. When a user connects to the database or a service process is needed, the process performs further initialization as needed.
To manage foreground processes, use the DBMS_PROCESS
package. The procedures in this package configure the number of foreground processes for a connection pool, start a connection pool, and stop a connection pool.
See Also:
-
Oracle Database Administrator’s Guide for a detailed description of managing a pre-created processes
-
Oracle Database Reference for information about the
USE_DEDICATED_BROKER
parameter, which determines how dedicated servers are spawned.TRUE
enables the listener to send the connection to a dedicated connection broker that spawns the dedicated server.FALSE
sets the listener to spawn a dedicated server directly.
126.2 DBMS_PROCESS Security Model
You must be granted the SYSDBA
administrative privilege to use the DBMS_PROCESS
package.
126.3 Summary of DBMS_PROCESS Subprograms
This table lists the DBMS_PROCESS
subprograms and briefly describes them.
Table 126-1 DBMS_PROCESS Package Subprograms
Subprogram | Description |
---|---|
Configures the minimum number of prespawned processes, the number of prespawned processes in a batch, and the initial number of pre-spawned processes for a foreground connection pool |
|
Starts a prespawned foreground process pool. |
|
Stops a prespawned foreground process pool. |
126.3.1 CONFIGURE_POOL Procedure
This procedure configures the minimum number of prespawned processes, the number of prespawned processes in a batch, and the initial number of pre-spawned processes for a foreground connection pool.
Syntax
DBMS_PROCESS.CONFIGURE_POOL( pool_name IN VARCHAR2 DEFAULT "SYS_DEFAULT_FOREGROUND_POOL", min_count IN NUMBER DEFAULT 10, batch_count IN NUMBER DEFAULT 20, init_count IN NUMBER DEFAULT 0);
Parameters
Table 126-2 CONFIGURE_POOL Procedure Parameters
Parameter | Description |
---|---|
|
Name of the foreground pool |
|
Count after which a batch of prespawned processes will be spawned in the pool (default 10; maximum number of processes 64,000) |
|
Batch of prespawned servers to be spawned in the pool (default 20). The total value of the |
|
Set of prespawned servers to be spawned in startup, or before a storm of connections, spawned in batches (default 0). Do not exceed the |
Exceptions
Table 126-3 CONFIGURE_POOL Procedure Exceptions
Error | Description |
---|---|
|
Prespawn not enabled |
|
Prespawn pool not found |
|
Prespawn pool already started |
|
Prespawn pool not started |
|
Process pool invalid configuration value(s) |
Usage Notes
-
To find information about foreground processes, query the
V$PROCESS_POOL
dynamic view.
Example
BEGIN DBMS_PROCESS.CONFIGURE_POOL ( pool_name => 'hrdb_pool', min_count => 40, batch_count => 20, init_count => 10); END; /
126.3.2 START_POOL Procedure
This procedure starts a prespawned foreground process pool.
Syntax
DBMS_PROCESS.START_POOL( pool_name IN VARCHAR2 DEFAULT "SYS_DEFAULT_FOREGROUND_POOL");
Parameters
Table 126-4 START_POOL Procedure Parameters
Parameter | Description |
---|---|
|
Name of prespawned foreground process pool. To find existing pools, query the |
Exceptions
Table 126-5 START_POOL Procedure Exceptions
Error | Description |
---|---|
|
Prespawn pool not found |
|
Prespawn pool already started |
|
Prespawn pool not started |
Example
BEGIN DBMS_PROCESS.START_POOL ( pool_name => 'hrdb_pool', END;
126.3.3 STOP_POOL Procedure
This procedure stops a prespawned foreground process pool.
Syntax
DBMS_PROCESS.STOP_POOL( pool_name IN VARCHAR2 DEFAULT "SYS_DEFAULT_FOREGROUND_POOL");
Parameters
Table 126-6 STOP_POOL Procedure Parameters
Parameter | Description |
---|---|
|
Name of the prespawned foreground process pool. To find existing pools, query the |
Exceptions
Table 126-7 STOP_POOL Procedure Exceptions
Error | Description |
---|---|
|
Prespawn pool not found |
|
Prespawn pool already started |
|
Prespawn pool not started |
Example
BEGIN DBMS_PROCESS.STOP_POOL ( pool_name => 'hrdb_pool', END;