Row cache lock (%)

Description

This metric is used to wait for a lock on a data dictionary cache specified by "cache id". If one is running in shared mode (Parallel Server), the LCK0 is signaled to get the row cache lock for the foreground waiting on this event. The LCK0 process will get the lock asynchronously. In exclusive mode, the foreground process will try to get the lock.

Metric Summary

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 'row cache lock' event.

Data Source

(DeltaRowCacheLockTime/DeltaServiceTime)*100 where:

See Idle Events

User Action

If this event shows up a lot, consider increasing the shared pool so that more data dictionary can be cached.

Related Topics

About Alerts

About the Metric Detail Page

Editing Thresholds

Understanding Line Charts