I/O per second

Description

This metric shows the sum of disks I/O performance per second in terms of total I/O requests for all the disks within the disk group. The data is displayed for all instances that are part of the cluster.

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.

Target Version

Collection Frequency

All Versions

Every 15 Minutes

Data Source

It is calculated using the Instance Disk Performance metric which in turn collects data from the GV$ASM_DISKGROUP and GV$ASM_DISK views for 10g Release 1 and the GV$ASM_DISKGROUP_STAT and GV$ASM_DISK_STAT views for 10g Release 2.

To calculate the average I/Os per second for each disk, the total number of I/O responses is divided by the total I/O time during the collection interval. This data is aggregated by the disk group name to get the average I/O operations per second of a disk group. The data is displayed for all instances that are part of the cluster.

User Action

No user action is required.

Related Topics

About Alerts

About the Metric Detail Page

Editing Thresholds

Understanding Line Charts