1 Cluster ASM Metrics

Open Instance Count

This metric shows the OSM instance count.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Status from gv$instance

User Action

No user action is required.

Disk Creation Date

This metric shows the disk creation date of the ASM disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

create_date from v$asm_disk_stat

User Action

No user action is required.

Disk Group Name

This metric shows the disk group name of the ASM disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from V$asm_diskgroup_stat

User Action

No user action is required.

Size (MB)

This metric shows the disk size in MB of the ASM disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from total_mb from v$asm_disk_stat

User Action

No user action is required.

Failure Group Type

This metric shows the failure group type, REGULAR or QUORUM.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

failgroup from v$asm_disk_stat

User Action

No user action is required.

Failure Group Name

This metric shows the failure group name of the ASM disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column SPACE in the V$ASM_FILE view

User Action

No user action is required.

Disk

This metric shows the disk name of the ASM disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

name from v$asm_disk_stat

User Action

No user action is required.

Disk Path

This metric shows the disk path of the ASM disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

path from v$asm_disk_stat

User Action

No user action is required.

Redundancy

This metric shows the level of redundancy of the ASM disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

redundancy from v$asm_disk_stat

User Action

No user action is required.

Allocation Unit (MB)

This metric shows the allocation unit size in MB of the ASM disk group

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

allocation_unit_size from v$asm_diskgroup_stat

User Action

No user action is required.

Disk Count

This metric shows the number of disks in the ASM disk group

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

count of disk from v$asm_disk_stat

User Action

No user action is required.

Disk Group

This metric shows the disk group name of the ASM disk group.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

name from v$Asm_diskgroup_stat

User Action

No user action is required.

Redundancy

This metric shows the level of redundancy of the ASM disk group.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

type from v$Asm_diskgroup_stat

User Action

No user action is required.

Size (GB)

This metric shows the ASM disk group size in GB.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

total_mb from v$Asm_diskgroup_stat

User Action

No user action is required.

Contains Voting Files

This metric shows whether there are voting files present.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

voting_files from v$Asm_diskgroup_stat

User Action

No user action is required.

Attribute Name

This metric shows the ASM disk group attribute name.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

name in v$asm_attribute

User Action

No user action is required.

Disk Group Name

This metric shows the ASM disk group name.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

name in v$Asm_diskgroup_stat

User Action

No user action is required.

Value

This metric shows the ASM disk group value.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

value in v$asm_attribute

User Action

No user action is required.

Default

This metric shows the default value for the ASM instance.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

isdefault from v$parameter

User Action

No user action is required.

Name

This metric shows the name of the ASM instance.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

name from v$parameter

User Action

No user action is required.

Value

This metric shows the value for the ASM instance.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

value from v$parameter

User Action

No user action is required.

Corrupt

This metric shows if the mounted ASM Cluster File System has sections that are corrupt. A value of "TRUE" for this metric indicates that there are sections that are corrupt and hence the "Check and Repair" operation should be run on the ASM Cluster File System to fix it. For dismounted ASM Cluster File Systems, it returns a value of Null for this metric.

This metric generates a warning alert if the ASM Cluster File System is dismounted on a given host. The metric also generates a critical alert if the mounted ASM Cluster File System is not available on a host.

This metric is collected at a time interval of 15 minutes. You can change the threshold limit as required.

This metric is collected with the help of a SQL query which queries the V$ASM_FILESYSTEM, V$ASM_VOLUME, V$ASM_OFSVOLUMES views.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric column you can set different warning and critical threshold values for each unique combination of "Volume Device" and "Disk Group" objects.

If warning or critical threshold values are currently set for any unique combination of "Volume Device" and "Disk Group" objects, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each unique combination of "Volume Device" and "Disk Group" objects, use the Edit Thresholds page.

Data Source

This metric is collected from the column CORRUPT in the V$ASM_FILESYSTEM view for mounted ASM Cluster File Systems. For Dismounted File Systems, a value of Null is returned for this metric.

User Action

Run Check and Repair on the ASM Cluster File System to fix the corrupted sections.

Disk Group Allocated Space (GB)

This metric shows the space allocated from the disk group for this ASM Cluster File System in GB.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column SPACE in the V$ASM_FILE view

User Action

No user action is required.

Free (GB)

This metric shows the unused capacity of the ASM Cluster File System in gigabytes. It gives an indication of the free space available in the ASM Cluster File System. For dismounted ASM Cluster File Systems, a value of 0 is returned for this metric.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column TOTAL_FREE in the V$ASM_FILESYSTEM view. For dismounted ASM Cluster File Systems, a value of 0 is returned.

User Action

Consider resizing the ASM Cluster File System if there is not enough Free Space available.

Size (GB)

This metric shows the Size in GB of the ASM Cluster File System.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column TOTAL_SIZE in the V$ASM_FILESYSTEM view for mounted File Systems and from the column SIZE_MB in the view V$ASM_VOLUME for dismounted File Systems.

User Action

Consider resizing the ASM Cluster File System to add space.

Used (GB)

This metric shows the Space in GB that is used on the mounted ASM Cluster File System. For dismounted ASM Cluster File Systems, a value of 0 is returned for this metric.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is calculated from the columns TOTAL_SIZE and TOTAL_FREE in the V$ASM_FILESYSTEM view. It is calculated as:

TOTAL_SIZE - TOTAL_FREE

For dismounted ASM Cluster File Systems, a value of 0 is returned for this metric

User Action

Consider Resizing the ASM Cluster File System to add more space.

Used (%)

This metric shows the percentage of Space that is used on the ASM Cluster File System. For dismounted ASM Cluster File Systems, a value of 0 is returned for this metric.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each unique combination of "Volume Device" and "Disk Group" objects.

If warning or critical threshold values are currently set for any unique combination of "Volume Device" and "Disk Group" objects, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each unique combination of "Volume Device" and "Disk Group" objects, use the Edit Thresholds page.

Data Source

This metric is calculated from the columns TOTAL_SIZE and TOTAL_FREE in the V$ASM_FILESYSTEM view. It is calculated as:

TOTAL_SIZE - TOTAL_FREE/TOTAL_SIZE * 100 

For dismounted ASM Cluster File Systems, a value of 0 is returned for this metric

User Action

Consider resizing the ASM Cluster File System to add more space to fix the alert generated by this metric.

Volume Name

This metric shows the Volume Name of the Volume Device used to create the ASM Cluster File System.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column VOLUME_NAME in the V$ASM_VOLUME view.

User Action

No user action is required.

ASM Cluster File System Availability

This metric shows if the MOUNTED ASM Cluster File System is AVAILABLE on a given host in a cluster. For DISMOUNTED ASM Cluster File System's this metric returns a value of NULL.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each unique combination of "Volume Device" and "Host" objects.

If warning or critical threshold values are currently set for any unique combination of "Volume Device" and "Host" objects, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each unique combination of "Volume Device" and "Host" objects, use the Edit Thresholds page.

Data Source

This metric is collected from the column STATE in the V$ASM_FILESYSTEM view.

User Action

No user action is required.

ASM Cluster File System Available Time

This metric shows the timestamp since which the MOUNTED ASM Cluster File System is AVAILABLE on a given host in a cluster. For DISMOUNTED ASM Cluster File System's this metric returns a value of NULL.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column AVAILABLE_TIME in the V$ASM_FILESYSTEM view.

User Action

No user action is required.

ACM Cluster File System Mount Point

This metric shows the mount point of the ASM Cluster File System on a given host in a cluster. The same ASM Cluster File System could be mounted on different mount points, on different hosts in a cluster. For DISMOUNTED ASM Cluster File Systems it will return NULL if the OFS has never been mounted on the host or it will return the last mount point if it was mounted and then dismounted on the host.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

For MOUNTED file systems this metric is collected from the column FS_NAME in the V$ASM_FILESYSTEM view. For DISMOUNTED file systems this metric is collected from the column MOUNTPATH in the V$ASM_VOLUME view.

User Action

No user action is required.

ASM Cluster File System Mount State

This metric shows the state of the ASM Cluster File Systems, whether it is MOUNTED or DISMOUNTED on a given host. In a cluster environment the ASM Cluster File System could be mounted only on specific hosts.

Metric Summary for Database Control and Cloud Control

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.

Multiple Threshold

For this metric you can set different warning and critical threshold values for each unique combination of "Volume Device" and "Host" objects.

If warning or critical threshold values are currently set for any unique combination of "Volume Device" and "Host" objects, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each unique combination of "Volume Device" and "Host" objects, use the Edit Thresholds page.

Data Source

An ASM Cluster File System is "MOUNTED" if the usage of the volume_device is "ACFS" and the volume_device exists in the V$ASM_ACFSVOLUMES view and the mount path exists in the V$ASM_FILESYSTEM view.

An ASM Cluster File System is "DISMOUNTED" if the usage of the volume_device is "ACFS" and the volume_device does not exist in the V$ASM_ACFSVOLUMES view and the mount path does not exist in the V$ASM_FILESYSTEM view.

User Action

Mount the ASM Cluster File System on the given host in the cluster

Disk Group Allocated Space (GB)

This metric gives the space in GB allocated on the disk group for the volume.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is retrieved from the column SPACE from the V$ASM_FILE view.

User Action

No user action is required.

Mount Point

An ASM Cluster File System is built on an ASM Volume which in turn uses ASM disk groups for storage. The ASM Cluster File System can then be mounted on any host in a cluster. This metric returns the current MOUNT POINT of the ASM Cluster File System if it is mounted or the most recent MOUNT POINT if it is currently DISMOUNTED. For ASM Volumes that are not used for ASM Cluster File Systems, this metric returns null.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is retrieved from the column MOUNTPATH from the V$ASM_VOLUME view.

User Action

No user action is required.

Redundancy

This metric returns the redundancy for the ASM Volume file. The ASM Volume file can use whatever redundancy (external, normal=2-way mirror, high=3-way mirror) is available to the ASM disk group where the ASM Volume file is created.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is retrieved from the REDUNDANCY column from the V$ASM_VOLUME view.

User Action

No user action is required.

Size (GB)

This metric returns the size of the ASM Volume in GB. The Volume Size is always created in multiples of the Volume Allocation Unit,

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is retrieved from the column SIZE_MB from the V$ASM_VOLUME view.

User Action

No user action is required.

Status

This metric shows the Status of the ASM Volume, if it is ENABLED or DISABLED.

Metric Summary

The following table shows how often the metric's value is collected.

Data Source

This metric is retrieved from the column STATE from the V$ASM_VOLUME view.

User Action

No user action is required.

Usage

This metric returns a string indicating what the ASM Volume is used for: ACFS, EXT3, null. A value of null means the usage of the Volume is Unknown.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric returns a string indicating what the ASM Volume is used for: ACFS, EXT3, null. A value of null means the usage of the Volume is Unknown.

User Action

No user action is required.

Volume Name

This metric returns the name of the ASM volume. This is the name entered when the user creates the ASM Volume on the disk group.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is retrieved from the column VOLUME_NAME from the view V$ASM_VOLUME view.

User Action

No user action is required.

Total Bytes

This metric shows the total bytes of the disk group space used by a database. With the help of this metric one can know the space used in a disk group by different database instance.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

We get the space used by a file using the V$ASM_FILE view and then it is joined with the V$ASM_ALIAS and V$ASM_DISKGROUP views for 10g Release 1 and the V$ASM_ALIAS, V$ASM_DISKGROUP_STAT views for 10g Release 2 to get the disk group space used by a database instance

User Action

No user action is required.

Actual Imbalance (%)

Actual Imbalance (%) measures the difference in space allocated to the fullest and emptiest disks in the disk group. Comparison is in percent full since ASM tries to keep all disks equally full as a percent of their size. The imbalance is relative to the space allocated not the space available. An imbalance of a couple percent is reasonable.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Actual Imbalance (%) is calculated as:

100 * (max((total_mb - free_mb) / total_mb) - min((total_mb - free_mb)
/ total_mb)) / max((total_mb - free_mb) / total_mb)
where total_mb and free_mb are columns in V$ASM_DISK_STAT

User Action

An imbalance of more than a couple percent may signal the need to initiate a manual rebalance of the disk group.

Actual Minimum Percent Free

Actual Minimum Percent Free lists the amount of free disk space on the fullest disk as a percentage of the disk size. If the imbalance is zero, then this represents the total free space. Since all allocations are done evenly across all disks, the minimum free space limits how much space can be used.

If one disk has only one percent free, then only one percent of the space in the disk group is really available for allocation, even if the rest of the disks are only half full

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Actual Minimum Percent Free is calculated as 100 * (min(free_mb / total_mb)), where free_mb and total_mb are columns in V$ASM_DISK_STAT.

User Action

If the actual minimum percent free is a low number, a configuration change may be required in order to provide an even distribution of file extents and space usage across all disks in a disk group.

Disk Count

Disk count is the number of disks in the disk group which gives a sense of how widely files can be spread.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Disk Count is calculated using count(*) on all disks (V$ASM_DISK_STAT) in a disk group (V$ASM_DISKGROUP_STAT).

User Action

No user action is required.

Disk Group Imbalance (%) without Rebalance

Disk Group Imbalance (%) without Rebalance is used to determine if a disk group requires rebalance. Temporary imbalances (caused by a rebalance in progress) are ignored.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group" object.

If warning or critical threshold values are currently set for any "Disk Group" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group" object, use the Edit Thresholds page.

Data Source

Disk Group Imbalance (%) without Rebalance is the same value as Actual Imbalance (%) if a rebalance operation is not in progress, 0 otherwise.

User Action

A warning alert will be generated if Disk Group Imbalance (%) without Rebalance is greater than or equal to 10%. In this case, a rebalance is necessary because the space usage imbalance between disks is high. The user should manually initiate a rebalance operation.

Disk Maximum Used (%) with Rebalance

Disk Maximum Used (%) with Rebalance is used to determine if a rebalance in progress needs a power boost to complete in a timely manner and prevent other errors from occurring due to space constraints.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group" object.

If warning or critical threshold values are currently set for any "Disk Group" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group" object, use the Edit Thresholds page.

Data Source

If a rebalance is in progress and the power value is greater than 0, then Disk Maximum Used (%) with Rebalance is calculated as (100 - Actual Minimum Percent Free), 0 otherwise.

User Action

A critical alert will be generated if Disk Maximum Used (%) with Rebalance is greater than or equal to 95%. In this case the rebalance power for the disk group must be increased because at least one disk is critically low on space. Increase the rebalance power (maximum power level is 11).

Disk Minimum Free (%) without Rebalance

Disk Minimum Free (%) without Rebalance is used to determine if a disk group requires rebalance. Temporary imbalances (caused by a rebalance in progress) are ignored.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group" object.

If warning or critical threshold values are currently set for any "Disk Group" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group" object, use the Edit Thresholds page.

Data Source

Disk Minimum Free (%) without Rebalance is the same value as Actual Minimum Percent Free if a rebalance operation is not in progress, 100 otherwise.

User Action

A warning alert will be generated if Disk Minimum Free (%) without Rebalance is less than or equal to 20%. In this case a rebalance is necessary because at least one disk is low on space. The user should manually initiate a rebalance operation.

Disk Size Variance (%)

Disk Size Variance (%) lists the percentage difference in size between the largest and smallest disks in the disk group. This will be zero if best practices have been followed and all disks are the same size.

Small differences in size are acceptable. Large differences can result in some disks getting much more I/O than others. With normal or high redundancy disk groups, a large size variance can make it impossible to reduce the percent imbalance to a small value.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Disk Size Variance (%) is calculated as 100 * 
(max(total_mb) - min(total_mb)) / max(total_mb), 
where total_mb is a column in V$ASM_DISK_STAT

User Action

A large size variance may require a configuration change to provide an even distribution of file extents and space usage across all disks in a disk group.

Rebalance In Progress

Rebalance In Progress returns "Yes" if a rebalance operation is in progress, "No" otherwise.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Rebalance In Progress is retrieved from the operation column of V$ASM_OPERATION.

User Action

No user action is required.

Disk Group Free (MB)

This metric shows the unused capacity of the disk group in megabytes. It gives an indication of the free space available in a disk group.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group Name" object.

If warning or critical threshold values are currently set for any "Disk Group Name" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group Name" object, use the Edit Thresholds page.

Data Source

This metric is collected from the column FREE_MB in the view V$ASM_DISKGROUP for 10g Release 1 and the V$ASM_DISKGROUP_STAT view for 10g Release 2.

User Action

Consider adding more disks to the disk group or deleting existing files in the disk group.

Disk Group Usable (Free MB)

The usable free space of a disk group depends on the redundancy, so in 10g Release 2 it uses the USABLE_FILE_MB column of the V$ASM_DISKGROUP_STAT view to indicate usable mirrored free space. This column indicates the amount of free space that can be "safely" utilized taking mirroring into account, and yet is able to restore redundancy after disk failure. This column is used to determine the usable free megabytes of a disk group.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group Name" object.

If warning or critical threshold values are currently set for any "Disk Group Name" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group Name" object, use the Edit Thresholds page.

Data Source

This metric is collected from the column USABLE_FILE_MB in the V$ASM_DISKGROUP_STAT view for 10g Release 2.

User Action

Consider adding more disks to the disk group or removing existing files from the disk group.

Disk Group Usable (MB)

This metric shows the capacity of the disk group based on the type of the disk group. This column indicates the amount of free space that can be "safely" utilized taking mirroring into account, and yet is able to restore redundancy after disk failure.

Metric Summary for Database Control and Cloud Control

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.

Data Source

This metric is collected using the V$ASM_DISKGROUP_STAT view.

Total Safely Usable MB = (total_mb - required_mirror_free_mb)/redundancy_factor

Where total_mb and required_mirror_free_mb come from the view column, and redundancy factor is 1 for External Redundancy Disk Group, 2 for Normal Redundancy Disk Group, and 3 for High Redundancy Disk Group.

User Action

Consider adding more disks to the disk group or removing existing files from the disk group

Disk Group Used %

This metric shows the percentage of space used by a disk group. It generates a warning alert if the disk group is 75% used and a critical warning if 90 % used. The threshold limit can be changed to generate alerts at different values.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group Name" object.

If warning or critical threshold values are currently set for any "Disk Group Name" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group Name" object, use the Edit Thresholds page.

Data Source

This metric is collected from the V$ASM_DISKGROUP view for 10g Release 1 and the V$ASM_DISKGROUP_STAT view for 10g Release 2.

Used % = (total_mb-free_mb)/total_mb)*100 

User Action

New disks can be added in a disk group to avoid the alerts. Go to the Disk Group general page and click Add to add a new disk to a disk group. Also, you can remove existing files from the disk group.

Redundancy

This metric shows the Redundancy Type of the disk group. It can be one of the three values: External, Normal, and High. This property determines the restore redundancy after disk failure.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column TYPE in the V$ASM_DISKGROUP view for 10g Release 1 and the V$ASM_DISKGROUP_STAT view for 10g Release 2.

User Action

No user action is required.

Size (MB)

This metric shows the total capacity of the disk group in megabytes. It gives an indication of the size or the space used by the disk group.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

This metric is collected from the column TOTAL_MB in the V$ASM_DISKGROUP view for 10g Release 1 and the V$ASM_DISKGROUP_STAT view for 10g Release 2.

User Action

Consider adding more disks to the disk group.

Used % of Safely Usable

This metric shows the percentage of safely usable space used by a disk group. Usable free space of a disk group depends on the redundancy. In 10g Release 2, it uses the USABLE_FILE_MB column of the V$ASM_DISKGROUP_STAT view to indicate usable mirrored free space. This column displays the amount of free space that can be safely utilized taking mirroring into account and restores redundancy after disk failure. This column is used to determine the "Used % of Safely Usable" for a disk group.

This metric generates a warning alert if the disk group is using 90% of the safely usable space and critical warning for 100%. The threshold limit can be changed to generate an alert at different values.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group Name" object.

If warning or critical threshold values are currently set for any "Disk Group Name" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group Name" object, use the Edit Thresholds page.

Data Source

This metric is collected from the V$ASM_DISKGROUP_STAT view for 10g Release 2.

Used % of Safely Usable = 100 - (usable_file_mb/usable_total_mb)*100 

Where usable_total_mb = total_mb - required_mirror_free_mb)/redundancy_factor 

total_mb and required_mirror_free_mb are derived from the view column and redundancy factor is 1 for External Redundancy Disk Group, 2 for Normal Redundancy Disk Group, and 3 for High Redundancy Disk Group.

User Action

New disks can be added in a disk group to avoid the alerts. Go to the Disk Group general page and click Add to add a new disk to a disk group. Also, you can remove existing files from the disk group.

Disk Name

This metric is the name of the disk path.

This metric is available in Database Control and Cloud Control; in target versions 10.2.0.x, 11.1.0.x, and 11 2.0.x.

Data Source

Name column value in the V$ASM_DISK_STAT and V$ASM_DISK views

User Action

No user action is required.

Disk Path

This metric is the physical path of the disk

This metric is available in Database Control and Cloud Control; in target versions 10.2.0.x, 11.1.0.x, and 11 2.0.x.

Data Source

Path column value. For databases prior to 10g Release 2, this metric uses the GV$ASM_DISK view. For databases 10g Release 2 and higher, this metric uses the GV$ASM_DISK_STAT view.

User Action

No user action is required.

Group Name

This metric provides the name of the group.

This metric is available in Database Control and Cloud Control; in target versions 10.2.0.x, 11.1.0.x, and 11 2.0.x.

Data Source

Path column value. For databases prior to 10g Release 2, this metric uses the GV$ASM_DISK view. For databases 10g Release 2 and higher, this metric uses the GV$ASM_DISK_STAT view.

User Action

No user action is required.

Disk Mode Status

This metric displays disk mode status (offline and online). A critical warning alert is generated if any of the disks go offline.

You can change the threshold limit.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each unique combination of "Disk Group Name" and "Disk Name" objects.

If warning or critical threshold values are currently set for any unique combination of "Disk Group Name" and "Disk Name" objects, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each unique combination of "Disk Group Name" and "Disk Name" objects, use the Edit Thresholds page.

Data Source

This metric is collected with the help view column mode status from GV$ASM_DISK for 10gRelease 1 and GV$ASM_DISK_STAT for 10g Release 2.

User Action

Try to bring the disk online. Currently Enterprise Manager does not support this feature

Disk Count Imbalance Variance

Failure groups are used to store mirror copies of data, two copies for normal redundancy, three copies for high redundancy. Disk Count Imbalance Variance gives the difference in the failure group disk count for the disk in the disk group with the highest failure group disk count and the disk with the lowest.

It may not be possible for every disk to have the same failure group disk count even when all the failure groups are the same size. However an imbalance of more than one indicates that the failure groups are different sizes.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group" object.

If warning or critical threshold values are currently set for any "Disk Group" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group" object, use the Edit Thresholds page.

Data Source

Disk Count Imbalance Variance is calculated using the V$ASM_DISKGROUP_STAT and V$ASM_DISK_STAT views, along with some internal ASM fixed tables.

User Action

A warning alert will be generated when the Disk Count Imbalance Variance is greater than 1 (by default). Disk groups that have failure groups with different numbers of disks may lead to suboptimal space usage. To alleviate this problem, try changing the configuration.

Disk Size Imbalance (%)

Disk Size Imbalance (%) checks if some disks have more space in their failure group disks than others. The space is calculated as a ratio between the size of a disk and the sum of the sizes of its active failure group disks. This ratio is compared for all the disks. The difference in the highest and lowest failure group disk space is reported as a percentage. An imbalance of 10% is acceptable.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each "Disk Group" object.

If warning or critical threshold values are currently set for any "Disk Group" object, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each "Disk Group" object, use the Edit Thresholds page.

Data Source

Disk Size Imbalance is calculated using the V$ASM_DISKGROUP_STAT and V$ASM_DISK_STAT views, along with some internal ASM fixed tables.

User Action

A warning alert will be generated when the Disk Size Imbalance (%) is greater than 10% (by default). Disk groups that have failure groups with disks of different sizes may lead to suboptimal space usage. To alleviate this problem, try changing the configuration.

Failure Group Count

Failure Group Count reports the number of failure groups per disk group.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Failure Group Count is retrieved from a calculation involving the V$ASM_DISKGROUP_STAT and V$ASM_DISK_STAT views, and some internal ASM fixed tables.

User Action

No user action is required.

Available Disks

Available Disks reports the number of disks in the failure group that are online.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Available Disks is calculated by subtracting the number of offline disks in the failure group from the number of total disks.

User Action

No user action is required.

Disk Count for Alerts

Disk Count for Alerts will have the same value as Available Disks if there is more than one disk in the failure group. If there is exactly one disk in the failure group, Disk Count for Alerts will be 1, regardless if that one disk is offline. The reason for this is to avoid duplicate alerts being generated for the same root cause. The disk_status metric will generate a critical alert when a disk goes offline.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each unique combination of "Disk Group" and "Failure Group" objects.

If warning or critical threshold values are currently set for any unique combination of "Disk Group" and "Failure Group" objects, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each unique combination of "Disk Group" and "Failure Group" objects, use the Edit Thresholds page.

Data Source

Disk Count for Alerts is set to 1 if there is only one disk in the disk group, otherwise it is set to the value of Available Disks.

User Action

A critical alert will be generated if all disks comprising a failure group are taken offline. In this situation, data is not being mirrored, despite the disk group having been configured with normal or high redundancy. Action must be taken to bring some of the disks in the failure group back online, or to add more disks to the disk group and assign them to that failure group.

Total Disks

Total Disks reports the number of disks in the failure group.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

Total Disks is retrieved from the V$ASM_DISKGROUP_STAT and V$ASM_DISK_STAT views.

User Action

No user action is required.

Bytes Read

This metric shows the total number of bytes read from the disk

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

It is calculated using the data from the GV$ASM_DISKGROUP_STAT and GV$ASM_DISK_STAT views.

User Action

No user action is required.

Bytes Written

This metric shows the total number of bytes written to the disk

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

It is calculated using the data from the GV$ASM_DISKGROUP_STAT and GV$ASM_DISK_STAT views.

User Action

No user action is required.

Read Time (MS)

This metric shows the total I/O time (in seconds) for read requests for the disk if the TIMED_STATISTICS initialization parameter is set to true (0 if set to false)

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

It is calculated using the data from the GV$ASM_DISKGROUP_STAT and GV$ASM_DISK_STAT views.

User Action

No user action is required.

Reads

This metric shows the total number of I/O read requests for the disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

It is calculated using the data from the GV$ASM_DISKGROUP_STAT and GV$ASM_DISK_STAT views.

User Action

No user action is required.

Write Time

This metric shows the total I/O time (in seconds) for write requests for the disk if the TIMED_STATISTICS initialization parameter is set to true (0 if set to false)

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

It is calculated using the data from the GV$ASM_DISKGROUP_STAT and GV$ASM_DISK_STAT views.

User Action

No user action is required.

Writes

This metric shows the total number of I/O write requests for the disk.

Metric Summary for Database Control and Cloud Control

The following table shows how often the metric's value is collected.

Data Source

It is calculated using the data from the GV$ASM_DISKGROUP_STAT and GV$ASM_DISK_STAT views.

User Action

No user action is required.

Read Write Errors

This metric shows the detail of the total number of failed read/writes for the disk. This provides information about the total number of failed attempts of reads and writes for the disk.

Metric Summary for Database Control and Cloud Control

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.

Multiple Thresholds

For this metric you can set different warning and critical threshold values for each unique combination of "Instance ID", "Disk Group Name", and "Disk Name" objects.

If warning or critical threshold values are currently set for any unique combination of "Instance ID", "Disk Group Name", and "Disk Name" objects, those thresholds can be viewed on the Metric Detail page for this metric.

To specify or change warning or critical threshold values for each unique combination of "Instance ID", "Disk Group Name", and "Disk Name" objects, use the Edit Thresholds page.

Data Source

It is calculated using 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. From these views, the total number of failed read/writes for the disk is added to calculate the read write errors detail.

User Action

Investigate the issues behind read/write errors.

Offline Disk Count

This metric provides the count of the disk with mode status offline. A critical alert is generated if the offline disk count changes or any of the disks go offline.

You can change the time limit and threshold limit as required.

Metric Summary for Database Control and Cloud Control

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.

Data Source

This metric is collected with the help of Disk Status 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.

User Action

Try to bring the disk online. Currently Enterprise Manager does not support this administration feature so it needs to be done manually.

Status

This metric shows the status of the Cluster ASM instance. It displays whether the instance is up or down. This check is performed every five minutes and returns the status of the connection as successful or it displays the ORA error for connection failure. Alert will be generated for individual ASM Instance that is down.

Metric Summary for Database Control and Cloud Control

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.

Data Source

You can establish a connection to the ASM instance with instance properties, and if the connection succeeds then the status is shown as Up, otherwise is displays as Down. It may also display as Down if there is an error in the metric collection.

User Action

Perform one of the following:

• Check that the configuration property saved for the ASM instance is correct.

• If it displays as Down, the ASM instance is down. Try to reestablish the connection using the startup/shutdown feature using the Enterprise Manager application. Alternately, you can restart the application manually.