The system is waiting for space in the log buffer because data is being written into the log buffer faster than LGWR can write it out.
The rest of the information in this section is only valid for this metric when it appears in either the Enterprise Manager Grid Control or the Enterprise Manager Database Control (if applicable).
The following table shows how often the metric's value is collected and compared against the default thresholds. The 'Consecutive Number of Occurrences Preceding Notification' column indicates the consecutive number of times the comparison against thresholds should hold TRUE before an alert is generated.
|
Target Version |
Evaluation and Collection Frequency |
Upload Frequency |
Operator |
Default Warning Threshold |
Default Critical Threshold |
Consecutive Number of Occurrences Preceding Notification |
Alert Text |
|
pre-10g |
Every Minute |
After Every Sample |
> |
20 |
Not Defined |
3 |
%value%%% of service time is spent waiting on the 'log buffer space' event. |
(DeltaLogBufferSpaceTime/DeltaServiceTime)*100 where:
DeltaLogBufferSpaceTime: difference of 'sum of time waited for sessions of foreground processes on the 'log buffer space' event' between sample end and start
DeltaServiceTime: difference of 'sum of time waited for sessions of foreground processes on events not in IdleEvents + sum of 'CPU used when call started' for sessions of foreground processes' between sample end and start
See Idle Events
Consider making the log buffer bigger if it is small, or moving the log files to faster disks such as striped disks.
Related Topics
About Alerts
About the Metric Detail Page
Editing Thresholds
Understanding Line Charts
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