53
DBMS_MONITOR

The DBMS_MONITOR package let you use PL/SQL for controlling additional tracing and statistics gathering.

The chapter contains the following topics:

• Summary of DBMS_MONITOR Subprograms

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Summary of DBMS_MONITOR Subprograms

Table 53-1  DBMS_MONITOR Package Subprograms  

Subprogram	Description
CLIENT_ID_STAT_DISABLE Procedure	Disables statistic gathering previously enabled for a given Client Identifier
CLIENT_ID_STAT_ENABLE Procedure	Enables statistic gathering for a given Client Identifier
CLIENT_ID_TRACE_DISABLE Procedure	Disables the trace previously enabled for a given Client Identifier globally for the database
CLIENT_ID_TRACE_ENABLE Procedure	Enables the trace for a given Client Identifier globally for the database
SERV_MOD_ACT_STAT_DISABLE Procedure	Disables statistic gathering enabled for a given combination of Service Name, MODULE and ACTION
SERV_MOD_ACT_STAT_ENABLE Procedure	Enables statistic gathering for a given combination of Service Name, MODULE and ACTION
SERV_MOD_ACT_TRACE_DISABLE Procedure	Disables the trace for ALL enabled instances for a or a given combination of Service Name, MODULE and ACTION name globally
SERV_MOD_ACT_TRACE_ENABLE Procedure	Enables SQL tracing for a given combination of Service Name, MODULE and ACTION globally unless an instance_name is specified
SESSION_TRACE_DISABLE Procedure	Disables the previously enabled trace for a given database session identifier (SID) on the local instance
SESSION_TRACE_ENABLE Procedure	Enables the trace for a given database session identifier (SID) on the local instance

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CLIENT_ID_STAT_DISABLE Procedure

This procedure will disable statistics accumulation for all instances and remove the accumulated results from V$CLIENT_STATS view enabled by the CLIENT_ID_STAT_ENABLE Procedure.

Syntax

DBMS_MONITOR.CLIENT_ID_STAT_DISABLE(
   client_id            IN   VARCHAR2);

Parameters

Table 53-2  CLIENT_ID_STAT_DISABLE Procedure Parameters

Parameter	Description
client_id	The Client Identifier for which statistic aggregation is disabled.

Examples

To disable accumulation:

EXECUTE DBMS_MONITOR.CLIENT_ID_STAT_DISABLE('janedoe');

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CLIENT_ID_STAT_ENABLE Procedure

This procedure enables statistic gathering for a given Client Identifier. Statistics gathering is global for the database and persistent across instance starts and restarts. That is, statistics are enabled for all instances of the same database, including restarts. Statistics are viewable through V$CLIENT_STATS views.

Syntax

DBMS_MONITOR.CLIENT_ID_STAT_ENABLE(
   client_id            IN   VARCHAR2);

Parameters

Table 53-3 CLIENT_ID_STAT_ENABLE Procedure Parameters

Parameter	Description
client_id	The Client Identifier for which statistic aggregation is enabled.

Examples

To enable statistic accumulation for a client with a given client ID:

EXECUTE DBMS_MONITOR.CLIENT_ID_STAT_ENABLE('janedoe');

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CLIENT_ID_TRACE_DISABLE Procedure

This procedure will disable tracing enabled by the CLIENT_ID_TRACE_ENABLE Procedure.

Syntax

DBMS_MONITOR.CLIENT_ID_TRACE_DISABLE(
 client_id            IN   VARCHAR2);

Parameters

Table 53-4  CLIENT_ID_TRACE_DISABLE Procedure Parameters

Parameter	Description
client_id	The Client Identifier for which SQL tracing is disabled.

Examples

EXECUTE DBMS_MONITOR.CLIENT_ID_TRACE_DISABLE ('janedoe');

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CLIENT_ID_TRACE_ENABLE Procedure

This procedure will enable the trace for a given client identifier globally for the database.

Syntax

DBMS_MONITOR.CLIENT_ID_TRACE_ENABLE(
   client_id    IN  VARCHAR2,
   waits        IN  BOOLEAN DEFAULT TRUE,
   binds        IN  BOOLEAN DEFAULT FALSE);

Parameters

Table 53-5  CLIENT_ID_TRACE_ENABLE Procedure Parameters

Parameter	Description
client_id	Database Session Identifier for which SQL tracing is enabled.
waits	If TRUE, wait information is present in the trace.
binds	If TRUE, bind information is present in the trace.

Usage Notes

• The trace will be written to multiple trace files because more than one Oracle shadow process can work on behalf of a given client identifier.
• The tracing is enabled for all instances and persistent across restarts.

Examples

EXECUTE DBMS_MONITOR.CLIENT_ID_TRACE_ENABLE('janedoe', TRUE,
FALSE);

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SERV_MOD_ACT_STAT_DISABLE Procedure

This procedure will disable statistics accumulation and remove the accumulated results from V$SERV_MOD_ACT_STATS view. Statistics disabling is persistent for the database. That is, service statistics are disabled for instances of the same database (plus dblinks that have been activated as a result of the enable).

Syntax

DBMS_MONITOR.SERV_MOD_ACT_STAT_DISABLE(
   service_name    IN VARCHAR2,
   module_name     IN VARCHAR2,
   action_name     IN VARCHAR2 DEFAULT ALL_ACTIONS);

Parameters

Table 53-6  SERV_MOD_ACT_STAT_DISABLE Procedure Parameters

Parameter	Description
service_name	Name of the service for which statistic aggregation is disabled.
module_name	Name of the MODULE. An additional qualifier for the service. It is a required parameter.
action_name	Name of the ACTION. An additional qualifier for the Service and MODULE name. Omitting the parameter (or supplying ALL_ACTIONS constant) means enabling aggregation for all Actions for a given Server/Module combination. In this case, statistics are aggregated on the module level.

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SERV_MOD_ACT_STAT_ENABLE Procedure

This procedure enables statistic gathering for a given combination of Service Name, MODULE and ACTION. Calling this procedure enables statistic gathering for a hierarchical combination of Service name, MODULE name, and ACTION name on all instances for the same database. Statistics are accessible by means of the V$SERV_MOD_ACT_STATS view.

Syntax

DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE(
   service_name    IN VARCHAR2,
   module_name     IN VARCHAR2,
   action_name     IN VARCHAR2 DEFAULT ALL_ACTIONS);

Parameters

Table 53-7  SERV_MOD_ACT_STAT_ENABLE Procedure Parameters

Parameter	Description
service_name	Name of the service for which statistic aggregation is enabled.
module_name	Name of the MODULE. An additional qualifier for the service. It is a required parameter.
action_name	Name of the ACTION. An additional qualifier for the Service and MODULE name. Omitting the parameter (or supplying ALL_ACTIONS constant) means enabling aggregation for all Actions for a given Server/Module combination. In this case, statistics are aggregated on the module level.

Usage Notes

Enabling statistic aggregation for the given combination of Service/Module/Action names is slightly complicated by the fact that the Module/Action values can be empty strings which are indistinguishable from NULLs. For this reason, we adopt the following conventions:

A special constant (unlikely to be a real action names) is defined:

ALL_ACTIONS constant VARCHAR2 := '###ALL_ACTIONS';

Using ALL_ACTIONS for a module specification means that aggregation is enabled for all actions with a given module name, while using NULL (or empty string) means that aggregation is enabled for an action whose name is an empty string.

Examples

To enable statistic accumulation for a given combination of Service name and MODULE:

EXECUTE DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE( 'APPS1','PAYROLL');

To enable statistic accumulation for a given combination of Service name, MODULE and ACTION:

EXECUTE
DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE('APPS1','GLEDGER','DEBIT_ENTRY');

If both of the preceding commands are issued, statistics are accumulated as follows:

• For the APPS1 service, because accumulation for each Service Name is the default.
• For all actions in the PAYROLL Module.
• For the DEBIT_ENTRY Action within the GLEDGER Module.

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SERV_MOD_ACT_TRACE_DISABLE Procedure

This procedure will disable the trace at ALL enabled instances for a given combination of Service Name, MODULE, and ACTION name globally.

Syntax

DBMS_MONITOR.SERV_MOD_ACT_TRACE_DISABLE(
   service_name    IN VARCHAR2,
   module_name     IN VARCHAR2,
   action_name     IN VARCHAR2 DEFAULT ALL_ACTIONS,
   instance_name   IN VARCHAR2 DEFAULT NULL);

Parameters

Table 53-8  SERV_MOD_ACT_TRACE_DISABLE Procedure Parameters

Parameter	Description
service_name	Name of the service for which tracing is disabled.
module_name	Name of the MODULE. An additional qualifier for the service.
action_name	Name of the ACTION. An additional qualifier for the Service and MODULE name.
instance_name	If set, this restricts tracing to the named instance_name.

Usage Notes

Specifying NULL for the module_name parameter means that statistics will no longer be accumulated for the sessions which do not set the MODULE attribute.

Examples

To enable tracing for a Service named APPS1:

EXECUTE DBMS_MONITOR.SERV_MOD_ACT_TRACE_ENABLE('APPS1',
            DBMS_MONITOR.ALL_MODULES,  DBMS_MONITOR.ALL_ACTIONS,TRUE,
FALSE,NULL);

To disable tracing specified in the previous step:

EXECUTE DBMS_MONITOR.SERV_MOD_ACT_TRACE_DISABLE('APPS1');

To enable tracing for a given combination of Service and MODULE (all ACTIONs):

EXECUTE DBMS_MONITOR.SERV_MOD_ACT_TRACE_ENABLE('APPS1','PAYROLL',
            DBMS_MONITOR.ALL_ACTIONS,TRUE,FALSE,NULL);

To disable tracing specified in the previous step:

EXECUTE DBMS_MONITOR.SERV_MOD_ACT_TRACE_DISABLE('APPS1','PAYROLL');

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SERV_MOD_ACT_TRACE_ENABLE Procedure

This procedure will enable SQL tracing for a given combination of Service Name, MODULE and ACTION globally unless an instance_name is specified.

Syntax

DBMS_MONITOR.SERV_MOD_ACT_TRACE_ENABLE(
   service_name    IN VARCHAR2,
   module_name     IN VARCHAR2 DEFAULT ANY_MODULE,
   action_name     IN VARCHAR2 DEFAULT ANY_ACTION,
   waits           IN BOOLEAN DEFAULT TRUE,
   binds           IN BOOLEAN DEFAULT FALSE,
   instance_name   IN VARCHAR2 DEFAULT NULL);

Parameters

Table 53-9  SERV_MOD_ACT_TRACE_ENABLE Procedure Parameters

Parameter	Description
service_name	Name of the service for which tracing is enabled.
module_name	Name of the MODULE. An optional additional qualifier for the service.
action_name	Name of the ACTION. An optional additional qualifier for the Service and MODULE name.
waits	If TRUE, wait information is present in the trace.
binds	If TRUE, bind information is present in the trace.
instance_name	If set, this restricts tracing to the named instance_name.

Usage Notes

• The procedure enables a trace for a given combination of Service, MODULE and ACTION name. The specification is strictly hierarchical: Service Name or Service Name/MODULE, or Service Name, MODULE, and ACTION name must be specified. Omitting a qualifier behaves like a wild-card, so that not specifying an ACTION means all ACTIONs. Using the ALL_ACTIONS constant achieves the same purpose.
• This tracing is useful when an application MODULE and optionally known ACTION is experiencing poor service levels.
• By default, tracing is enabled globally for the database. The instance_name parameter is provided to restrict tracing to named instances that are known, for example, to exhibit poor service levels.
• Tracing information is present in multiple trace files and you must use the trcsess tool to collect it into a single file.
• Specifying NULL for the module_name parameter means that statistics will be accumulated for the sessions which do not set the MODULE attribute.

Examples

To enable tracing for a Service named APPS1:

EXECUTE DBMS_MONITOR.SERV_MOD_ACT_TRACE_ENABLE('APPS1',
            DBMS_MONITOR.ALL_MODULES,  DBMS_MONITOR.ALL_ACTIONS,TRUE,
FALSE,NULL);

To enable tracing for a given combination of Service and MODULE (all ACTIONs):

EXECUTE DBMS_MONITOR.SERV_MOD_ACT_TRACE_ENABLE('APPS1','PAYROLL',
            DBMS_MONITOR.ALL_ACTIONS,TRUE,FALSE,NULL);

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SESSION_TRACE_DISABLE Procedure

This procedure will disable the trace for a given database session at the local instance.

Syntax

DBMS_MONITOR.SESSION_TRACE_DISABLE(
   session_id      IN     BINARY_INTEGER DEFAULT NULL,
   serial_num      IN     BINARY_INTEGER DEFAULT NULL);

Parameters

Table 53-10  SESSION_TRACE_DISABLE Procedure Parameters

Parameter	Description
session_id	Name of the service for which SQL trace is disabled.
serial_num	Serial number for this session.

Usage Notes

If serial_num is NULL but session_id is specified, a session with a given session_id is no longer traced irrespective of its serial number. If both session_id and serial_num are NULL, the current user session is no longer traced. It is illegal to specify NULL session_id and non-NULL serial_num. In addition, the NULL values are default and can be omitted.

Examples

To enable tracing for a client with a given client session ID:

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(7,4634, TRUE, FALSE);

To disable tracing specified in the previous step:

EXECUTE DBMS_MONITOR.SESSION_TRACE_DISABLE(7,4634);;

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SESSION_TRACE_ENABLE Procedure

This procedure enables a SQL trace for the given Session ID on the local instance

Syntax

DBMS_MONITOR.SESSION_TRACE_ENABLE(
    session_id   IN  BINARY_INTEGER DEFAULT NULL,
    serial_num   IN  BINARY_INTEGER DEFAULT NULL,
    waits        IN  BOOLEAN DEFAULT TRUE,
    binds        IN  BOOLEAN DEFAULT FALSE)

Parameters

Table 53-11  SESSION_TRACE_ENABLE Procedure Parameters

Parameter	Description
session_id	Database Session Identifier for which SQL tracing is enabled.
serial_num	Serial number for this session.
waits	If TRUE, wait information is present in the trace.
binds	If TRUE, bind information is present in the trace.

Usage Notes

The procedure enables a trace for a given database session, and is still useful for client/server applications. The trace is enabled only on the instance to which the caller is connected, since database sessions do not span instances. This tracing is strictly local to an instance.

If serial_num is NULL but session_id is specified, a session with a given session_id is traced irrespective of its serial number. If both session_id and serial_num are NULL, the current user session is traced. It is illegal to specify NULL session_id and non-NULL serial_num. In addition, the NULL values are default and can be omitted.

Examples

To enable tracing for a client with a given client session ID:

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(7,4634, TRUE, FALSE);

To disable tracing specified in the previous step:

EXECUTE DBMS_MONITOR.SESSION_TRACE_DISABLE(7,4634);

Either

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(5);

or

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(5, NULL);

traces the session with session ID of 5, while either

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE();

or

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(NULL, NULL);

traces the current user session. Also,

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(NULL, NULL, TRUE, TRUE);

traces the current user session including waits and binds. The same can be also expressed using keyword syntax:

EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(binds=>TRUE);