The ORA_DB02_LTCH event is used in SAP to view Oracle latch activity. A latch is a low-level serialization mechanism to protect shared data structures by preventing concurrent access to shared data structures in the Shared Global Area (SGA). Processes often have to wait to obtain a latch in order to access the data, which wastes CPU cycles.
Potential Use Cases
This event could be used in the following scenarios:
Alert on a high ratio of misses/gets for latch waits.
Trend latch wait percentages overtime.
Correlate latch waits with other events in the SAP ecosystem.
The event will look like this in Splunk:
Log into the managed system and execute the dbacockpit transaction code. Then expand the Performance menu option on the left side of the screen, and then expand the Wait Event Analysis menu option. Double-click the Enqueue Stat option. The data displayed will match the data that is extracted and sent to Splunk.
Unit of Measure
The date time stamp when the information was collected
Oracle monitoring: Latch Gets
Oracle monitoring: Latch Immediate Gets
Oracle monitoring: Latch Immediate Misses
Oracle monitor: Instance ID
Oracle monitoring: Latch Misses
Oracle monitoring: Name
Oracle Monitoring: GV$LATCH % of sleeps
Oracle Monitoring: GV$LATCH % wait time
Oracle Monitoring: GV$LATCH ratio misses / gets
Oracle monitoring: Latch Sleep 1
Oracle monitoring: Latch Sleep 2
Oracle monitoring: Latch Sleep 3
Oracle monitoring: Latch Sleep 4
Oracle monitoring: Latch Sleeps
Oracle monitoring: Latch Spin Gets
The UTC OFFSSET in HHMMSS that the data was collected in
The UTC positive or negative OFFSET indicator. Positive (+) means add UTCDIFF to find the time zone of the data, negative (-) means subtract the UTCDIFF to find the time zone adjusted date time the data was collected in.
+ | -
Oracle monitoring: Latch Wait Time