Indicates the number of data pages for XML storage objects (XDAs) read in from the table space containers (physical) for regular and large table spaces.
Snapshot Level | Logical Data Grouping | Monitor Switch |
---|---|---|
Database | dbase | Buffer Pool |
Table Space | tablespace | Buffer Pool |
Buffer Pool | bufferpool | Buffer Pool |
Application | appl | Buffer Pool |
Application | stmt | Buffer Pool |
Dynamic SQL | dynsql | Buffer Pool, Statement |
Event Type | Logical Data Grouping | Monitor Switch |
---|---|---|
Activities | event_activity (reported in the details_xml document) | ACTIVITY METRICS BASE |
Activities | event_activitymetrics | ACTIVITY METRICS BASE |
Statistics | event_scstats (reported in the metrics document) | REQUEST METRICS BASE |
Statistics | event_wlstats (reported in the metrics document) | REQUEST METRICS BASE |
Unit of work | Reported in the system_metrics document. | REQUEST METRICS BASE |
Database | event_db | - |
Tablespaces | event_tablespace | - |
Connection | event_conn | - |
Statement | event_stmt | - |
Activities | event_activity | Buffer Pool, Statement |
Package cache | Reported in the activity_metrics document. | ACTIVITY METRICS BASE |
Statistics | event_scmetrics* | REQUEST METRICS BASE |
Statistics | event_wlmetrics* | REQUEST METRICS BASE |
* When returned as part of this logical data group, this element reflects the change in value of this metric since the last statistics collection or database activation, whichever was more recent. |
pool_xda_p_reads + pool_temp_xda_p_reads - pool_async_xda_reads
By comparing the ratio of asynchronous to synchronous reads, you can gain insight into how well the prefetchers are working. This element can be helpful when you are tuning the num_ioservers configuration parameter.
1 - ((pool_data_p_reads + pool_xda_p_reads)
/ (pool_data_l_reads + pool_xda_l_reads))