Oracle tries to find the load lock for the database object so that it can load the object. The load lock is always gotten in Exclusive mode, so that no other process can load the same object. If the load lock is busy the session will wait on this event until the lock becomes available.
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 'library cache load lock' event. |
(DeltaLibraryCacheLoadLockTime/DeltaServiceTime)*100 where:
DeltaLibraryCacheLoadLockTime: difference of 'sum of time waited for sessions of foreground processes on the 'library cache load lock' 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
To be waiting for a load lock means that there is a blocker with a higher or incompatible mode. This event in itself is not affected by the parallel server. However, you must have acquired the 'library cache lock' before you get to this point. The 'cache lock' is a DFS lock.
Related Topics
About Alerts
About the Metric Detail Page
Editing Thresholds
Understanding Line Charts
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