X

x_lock_escals - Exclusive lock escalations monitor element

The number of times that locks have been escalated from several row locks to one exclusive table lock, or the number of times an exclusive lock on a row caused the table lock to become an exclusive lock.

Table 1. Snapshot Monitoring Information
Snapshot Level	Logical Data Grouping	Monitor Switch
Database	dbase	Basic
Application	appl	Basic

For snapshot monitoring, this counter can be reset.

Table 2. Event Monitoring Information
Event Type	Logical Data Grouping	Monitor Switch
Database	event_db	Always collected
Connection	event_conn	Always collected
Transactions	event_xact	Always collected

Usage

Other applications cannot access data held by an exclusive lock; therefore it is important to track exclusive locks since they can impact the concurrency of your data.

A lock is escalated when the total number of locks held by an application reaches the maximum amount of lock list space available to the application. The amount of lock list space available is determined by the locklist and maxlocks configuration parameters.

When an application reaches the maximum number of locks allowed and there are no more locks to escalate, it will then use space in the lock list allocated for other applications. When the entire lock list is full, an error occurs.

See the lock_escals monitor element for possible causes and resolutions to excessive exclusive lock escalations.

An application may be using exclusive locks when share locks are sufficient. Although share locks may not reduce the total number of lock escalations share lock escalations may be preferable to exclusive lock escalations.

xda_object_pages - XDA Object Pages monitor element

The number of disk pages consumed by XML storage object (XDA) data.

Element identifier: xda_object_pages
Element type: information

Table 3. Snapshot Monitoring Information
Snapshot Level	Logical Data Grouping	Monitor Switch
Table	table	Basic

Table 4. Event Monitoring Information
Event Type	Logical Data Grouping	Monitor Switch
Tables	event_table	Always collected

Usage: This element provides a mechanism for viewing the actual amount of space consumed by XML storage object (XDA) data in a particular table. This element can be used in conjunction with a table event monitor to track the rate of XML storage object data growth over time.

xda_object_l_pages - XML storage object (XDA) data logical pages monitor element

The number of logical pages used on disk by XML storage object (XDA) data.

Table 5. Table Function Monitoring Information
Table Function	Monitor Element Collection Level
MON_GET_TABLE table function - Get table metrics	Always collected

Usage

This value might be less than the amount of space physically allocated for the object. This can happen when you use the REUSE STORAGE option of the TRUNCATE statement. This option causes storage allocated for the table to continue to be allocated, although the storage will be considered empty. In addition, the value for this monitor element might be less than the amount of space logically allocated for the object, because the total space logically allocated includes a small amount of additional meta data.
To retrieve an accurate measure of the logical or physical size of an object, use the ADMIN_GET_TAB_INFO_V97 function. This function provides more accurate information about the size of objects than you can obtain by multiplying the number of pages reported for this monitor element by the page size.

xid - Transaction ID monitor element

A unique transaction identifier (across all databases) generated by a transaction manager in a two-phase commit transaction.

Table 6. Snapshot Monitoring Information
Snapshot Level	Logical Data Grouping	Monitor Switch
DCS Application	dcs_appl	Unit of Work

Usage: This identifier can be used to correlate the transaction generated by the transaction manager with the transactions executed against multiple databases. It can be used to help diagnose transaction manager problems by tying database transactions involving a two-phase commit protocol with the transactions originated by the transaction manager.

xmlid - XML ID monitor element

A unique document ID. The ID is derived as follows: <event_header>_<event_id>_<event_type>_<event_timestamp>_<partition>.

Table 7. Table Function Monitoring Information
Table Function	Monitor Element Collection Level
EVMON_FORMAT_UE_TO_TABLES procedure - move an XML document to relational tables	Not applicable; reports whichever elements are in the XML document that is provided as input to the formatting function.
EVMON_FORMAT_UE_TO_XML table function - convert unformatted events to XML	Not applicable; reports whichever elements are in the XML document that is provided as input to the formatting function.

Table 8. Event Monitoring Information
Event Type	Logical Data Grouping	Monitor Switch
Locking
Package Cache

xquery_stmts - XQuery Statements Attempted monitor element

The number of XQuery statements executed for an application or database.

Table 9. Table function monitoring information
Table function	Monitor element collection level
MON_GET_CONNECTION table function - Get connection metrics	REQUEST METRICS BASE
MON_GET_CONNECTION_DETAILS table function - Get detailed connection metrics (reported in DETAILS XML document)	REQUEST METRICS BASE
MON_GET_DATABASE table function - Get database level information	REQUEST METRICS BASE
MON_GET_DATABASE_DETAILS table function - Get database information metrics	REQUEST METRICS BASE
MON_GET_ROUTINE table function - get aggregated execution metrics for routines	REQUEST METRICS BASE
MON_GET_ROUTINE_DETAILS table function - get aggregated execution metric details for routines	REQUEST METRICS BASE
MON_GET_SERVICE_SUBCLASS table function - Get service subclass metrics	REQUEST METRICS BASE
MON_GET_SERVICE_SUBCLASS_DETAILS table function - Get detailed service subclass metrics	REQUEST METRICS BASE
MON_GET_UNIT_OF_WORK table function - Get unit of work metrics	REQUEST METRICS BASE
MON_GET_UNIT_OF_WORK_DETAILS table function - Get detailed unit of work metrics (reported in DETAILS XML document)	REQUEST METRICS BASE
MON_GET_WORKLOAD table function - Get workload metrics	REQUEST METRICS BASE
MON_GET_WORKLOAD_DETAILS table function - Get detailed workload metrics	REQUEST METRICS BASE

Table 10. Snapshot Monitoring Information
Snapshot Level	Logical Data Grouping	Monitor Switch
Database	dbase	Basic
Application	appl	Basic

For snapshot monitoring, this counter can be reset.

Table 11. Event Monitoring Information
Event Type	Logical Data Grouping	Monitor Switch
Connection	event_conn	Always collected
Database	event_db	Always collected
Statistics	event_scmetrics	REQUEST METRICS BASE
Statistics	event_wlmmetrics	REQUEST METRICS BASE
Unit of work	uow_metrics	REQUEST METRICS BASE

Usage: You can use this element to gauge the activity of native XQuery language requests. This does not include embedded XQuery language requests such as xmlquery, xmltable, or xmlexist.