System / Wait Events 
Definition
This submonitor in the SAP/Oracle Database Monitor lets you check the following wait events and system events in the Oracle database:
· Busy waits summary
· Wait event details
· Oracle view GV$SYSTEM_EVENT
Use
You choose Detailed Analyses ® Overall activity ® System / Wait Events and the required tab page Busy Waits Summary, Wait event details, or GV$SYSTEM_EVENT.
You can view history information in this monitor.
Structure
Entries marked “RAC only” appear only for Oracle Real Application Cluster (RAC)
· Busy Waits Summary
This tab page displays a summary of busy waits:
Column |
Description |
Inst Id RAC only |
Database instance ID |
Session type |
Type of session. For example, BACKGROUND for system sessions, USER for application sessions. |
User Name |
Name of the user connected to the database. For example, SAP applications connect as user SAPR3. |
PName |
Process name |
Sessions |
Number of sessions connected to the database |
Busy wait time (ms) |
Wait time spent busy in milliseconds |
Total wait time (ms) |
Total time waiting for an event in milliseconds |
Busy W (%) |
Busy wait time as percentage of Total wait time |
· Wait event details
This tab page displays details of wait events:
Column |
Description |
Inst ID RAC only |
Database instance ID |
Event |
Name of the event that caused the wait |
Wait time (ms) |
Time waiting for the event in milliseconds |
% of non-idle |
Percentage of non-idle waiting time caused by this event |
% of tot. resp. |
Percentage of total response time caused by this event |
Waits |
Number of waits |
Timeouts |
Number of timeouts |
Avg. WT (ms) |
Average wait time in milliseconds |
· GV$SYSTEM_EVENT
This tab page displays details from the Oracle view GV$SYSTEM_EVENT:
Column |
Description |
Event |
Name of the event that caused the wait |
Inst ID RAC only |
Database instance ID |
Wait time (ms) |
Time waiting for the event in milliseconds |
Wait% Inst/Evt. |
Percentage of time spent waiting for an event |
Waits |
Number of waits |
Timeouts |
Number of timeouts |
Avg. WT (ms) |
Average wait time in milliseconds |
This tab page shows events and wait times per instance in descending order of the event’s total wait time.
In a RAC environment, you see by default the wait times for each instance and the total wait times for all instances. If required, you can restrict the display to a single instance.