This metric represents the total rate of I/O read and write requests for the database.
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 |
11.1.0.x; 11.2.0.x |
Not Defined |
After Every Sample |
> |
Not Defined |
Not Defined |
2 |
Not Defined |
v$sysmetric
A high I/O request rate is not in itself problematic. However, if high I/O latencies (for example, Synchronous Single-Block Read Latencies) are causing a performance problem, then reducing the total I/O request rate may help. The source of the I/O requests can be investigated by viewing a breakdown by either Component or Resource Consumer Group.
Related Topics
About Alerts
About the Metric Detail Page
Editing Thresholds
Understanding Line Charts
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