1 Cluster ASM Metrics

This chapter provides information about the Cluster Automatic Storage Management (ASM) metrics.

1.1 ASM Cardinality

This metric category collects the number of ASM instances that are part of Cluster ASM. The default collection time is every five minutes.

1.1.1 Open Instance Count

This metric shows the ASM open instance count.

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

Data Source

The data source is the status column in the gv$instance view.

User Action

No user action is required.

1.2 ASM Cluster File System

The metrics in the ASM Cluster File System metric category show the space used by all of the ASM Cluster File Systems. These metrics are used to collect information about the ASM Cluster File System space usage and are used to show the trend of ASM Cluster File System space usage in the application. These metrics collect information for both mounted and dismounted ASM Cluster File Systems. This information is used to determine the following metrics for space usage: Allocated Space (GB), Size (GB), Free (GB), Used (GB), and Used (%). These metrics also collect information about whether the ASM Cluster File System is corrupt. For dismounted ASM Cluster File Systems, 0 is returned for the Free (GB), Used (GB), and Used (%) metrics.

These metrics only collect information about the ASM Cluster File System that is not specific to a node in a cluster. They collect space usage information which is the same across all nodes in the cluster. Information such as the state and availability of the ASM Cluster File System can be different across the nodes in a cluster and is collected by the ASM Cluster File System State metrics.

These metrics generate a warning alert if the ASM Cluster File System is 85% used and a critical alert if 97% used. These metrics also generate a critical alert if the ASM Cluster File System has sections that are corrupt.

These metrics are collected at a time interval of 15 minutes and the metrics will be collected at the cluster level if the target is Cluster ASM otherwise they will be collected at the instance level as a part of the ASM target type metrics. You can change the threshold limit as required.

1.2.1 ASM Cluster File System 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 therefore 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
11gR2, 12c	Every 30 Minutes	Not Defined	TRUE	The ASM Cluster File System using volume device %ofs_volume_device% has sections that are corrupt. Run check and repair operation on the file system to fix the issue.

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.

1.2.2 ASM Cluster File System Used (%)

This metric shows if the percent of the ASM cluster file system that is used.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
11gR2, 12cR1	Every 30 Minutes	Not Defined	TRUE	The ASM Cluster File System using volume device %ofs_volume_device% has sections that are corrupt. Run check and repair operation on the file system to fix the issue.

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.

1.2.3 Allocated Space (GB)

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

Target Version	Collection Frequency
11gR2, 12c	Every 30 Minutes

Data Source

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

User Action

No user action is required.

1.2.4 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.

Target Version	Collection Frequency
11gR2, 12c	Every 30 Minutes

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.

1.2.5 Size (GB)

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

Target Version	Collection Frequency
11gR2, 12c	Every 30 Minutes

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.

1.2.6 Snapshot Space Used (MB)

This metric shows the percentage of snapshot 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.

Target Version	Collection Frequency
11gR2, 12c	Every 30 Minutes

1.2.7 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.

Target Version	Collection Frequency
11gR2, 12c	Every 30 Minutes

Data Source

This metric is calculated from the columns TOTAL_SIZE and TOTAL_FREE in the V$ASM_FILESYSTEM view. This metric is calculated using the following formula:

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.

1.2.8 Used (MB)

This metric shows the space in MB 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.

Target Version	Collection Frequency
11gR2, 12c	Every 30 Minutes

Data Source

This metric is calculated from the columns TOTAL_SIZE and TOTAL_FREE in the V$ASM_FILESYSTEM view. This metric is calculated using the following formula:

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.

1.2.9 Volume Name

This metric shows the volume name of the volume device used to create the ASM Cluster File System.

Target Version	Collection Frequency
11gR2, 12c	Every 30 Minutes

Data Source

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

User Action

No user action is required.

1.3 ASM Cluster File System State

The metrics in the ASM Cluster File System State metric category show the state of the ASM Cluster File System, 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. If the ASM Cluster File System is mounted on a given host, the metrics also reports whether the system is available and the time since it was available. This is used to determine the following metrics: Mount Point, Mount State, Availability, and Available Time.

These metrics generate a warning alert if the ASM Cluster File System is dismounted on a given host. These metrics also generate a critical alert if the mounted ASM Cluster File System is not available on a host.

These metrics are collected with the help of a SQL query which queries the V$ASM_FILESYSTEM, V$ASM_VOLUME, V$ASM_OFSVOLUMES views. If the target is Cluster ASM the metrics will be collected at cluster level, otherwise they will be collected at instance level as a part of ASM target type metrics.

1.3.1 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
11gR2, 12c	Every 15 Minutes	Not Defined	Not Available	The ASM Cluster File System %ofs_mount_point% is not available on host %ofs_host%

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.

1.3.2 ASM Cluster File System Available Time

This metric shows the time since the mounted ASM Cluster File System has been available on a given host in a cluster. For dismounted ASM Cluster File Systems this metric returns a value of NULL.

Target Version	Collection Frequency	Alert Text
11gR2, 12c	Every 15 Minutes	The volume device %volume_device% is dismounted on host %ofs_host%

Data Source

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

User Action

No user action is required.

1.3.3 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.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

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.

1.3.4 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
11gR2, 12c	Every 15 Minutes	Dismounted	Not Defined	The volume device %volume_device% is dismounted on host %ofs_host%

Multiple Thresholds

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.

1.4 ASM Disk

The metrics in this configuration metric category collect ASM disk configuration data such as the disk group name. The default collection time is 24 hours and the metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.4.1 Disk

This metric shows the disk name of the ASM disk.

Target Version	Collection Frequency
10g 11g, 12cR1	Every 24 hours

Data Source

The source for this metric is the NAME column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.4.2 Disk Creation Date

This metric shows the creation date of the ASM disk.

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 24 hours

Data Source

The source for this metric is the CREATE_DATE column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.4.3 Disk Group

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

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 24 hours

Data Source

This metric is collected from V$ASM_DISKGROUP_STAT view.

User Action

No user action is required.

1.4.4 Disk Path

This metric shows the disk path of the ASM disk.

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 24 hours

Data Source

The source for this metric is the PATH column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.4.5 Fail Group Type

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

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 24 hours

Data Source

The source for this metric is the FAILUREGROUP column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.4.6 Failure Group

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

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 24 hours

Data Source

The source for this metric is the SPACE column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.4.7 Redundancy

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

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 24 hours

Data Source

The source for this metric is the REDUNANCY column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.4.8 Size (MB)

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

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 24 hours

Data Source

The source for this metric is the TOTAL_MB column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.5 ASM Disk Group

The metrics in this configuration metric category collect ASM disk group configuration data such as member disk count, redundancy, and ASM and database compatibility. The default collection time is 24 hours and the metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.5.1 Allocation Unit (MB)

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

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 hours

Data Source

The source for this metric is the ALLOCATION_UNIT_SIZE column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.5.2 Contains Voting Files

This metric shows whether there are voting files present.

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the VOTING_FILES column in the V$ASM_DISKGROUP_STAT view.

User Action

No user action is required.

1.5.3 Disk Count

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

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the COUNT_OF_DISK column in the V$ASM_DISK_STAT view.

User Action

No user action is required.

1.5.4 Disk Group

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

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the NAME column in the V$ASM_DISKGROUP_STAT view.

User Action

No user action is required.

1.5.5 Redundancy

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

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the TYPE column in the V$ASM_DISKGROUP_STAT view.

User Action

No user action is required.

1.5.6 Size (GB)

This metric shows the ASM disk group size in GB.

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the TOTAL_MB column in the V$ASM_DISKGROUP_STAT view.

User Action

No user action is required.

1.6 ASM Disk Group Attributes

The metrics in this configuration metric category collect ASM disk group Attribute data such as file access control, cell scan capability etc. The default collect time is 24 hours and the metrics will be collected at cluster level if the target is Cluster ASM, else they will be collected at instance level as a part of the ASM target type metrics.

1.6.1 Attribute Name

This metric shows the ASM disk group attribute name.

Target Version	Collection Frequency
11g, 12cR1	Every 24 Hours

Data Source

The source for this metric is the NAME column in the V$ASM_ATTRIBUTE view.

User Action

No user action is required.

1.6.2 Disk Group Name

This metric shows the ASM disk group name.

Target Version	Collection Frequency
11g, 12cR1	Every 24 Hours

Data Source

The source for this metric is the NAME column in the V$ASM_DISKGROUP_STAT view.

User Action

No user action is required.

1.6.3 Value

This metric shows the ASM disk group value.

Target Version	Collection Frequency
11g, 12cR1	Every 24 Hours

Data Source

The source for this metric is the VALUE column in the V$ASM_ATTRIBUTE view.

User Action

No user action is required.

1.7 ASM INIT Params

The metrics in this configuration metric category collect initialization parameters for the ASM instance. The default collection time is 24 hours and the metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.7.1 Default

This metric shows the default value for the ASM instance.

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the ISDEFAULT column in the V$PARAMETER view.

User Action

No user action is required.

1.7.2 Name

This metric shows the name of the ASM instance.

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the NAME column in the V$PARAMETER view.

User Action

No user action is required.

1.7.3 Value

This metric shows the value for the ASM instance.

Target Version	Collection Frequency
11gR2, 12cR1	Every 24 Hours

Data Source

The source for this metric is the VALUE column in the V$PARAMETER view.

User Action

No user action is required.

1.8 ASM Volumes

The metrics in the ASM Volumes metric category show information about the volumes created on a disk group. An ASM volume file is a file created on the disk group to provide storage for an ASM Cluster File System or a third-party file system. This is used to determine the following metrics for ASM volumes: Volume Name, Status, Usage, Mount Point, Size (GB), Allocated Space (GB), and Redundancy.

These metrics are collected with the help of the V$ASM_VOLUME and GV$ASM_DISKGROUP views. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.8.1 Allocated Space (GB)

This metric shows the space in MB allocated to the ASM Cluster File System on a given host in a cluster.

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

Data Source

The source of this metric is the MOUNTPATH column in the V$ASM_VOLUME view.

User Action

No user action is required.

1.8.2 Mount Point

This metric shows the mount point of the ASM Cluster File System on a given host in a cluster.

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

Data Source

The source of this metric is the MOUNTPATH column in the V$ASM_VOLUME view.

User Action

No user action is required.

1.8.3 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.

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

Data Source

The source of this metric is the REDUNDANCY column in the V$ASM_VOLUME view.

User Action

No user action is required.

1.8.4 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.

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

Data Source

The source of this metric is the column SIZE_MB from the V$ASM_VOLUME view.

User Action

No user action is required.

1.8.5 Status

This metric shows the Status of the ASM Volume, if it is enabled or disabled.

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

Data Source

The source of this metric is the column STATE from the V$ASM_VOLUME view.

User Action

No user action is required.

1.8.6 Usage

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

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

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.

1.8.7 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.

Target Version	Collection Frequency
11gR2, 12c	Every 24 hours

Data Source

The source of this metric is the VOLUME_NAME column in the V$ASM_VOLUME view.

User Action

No user action is required.

1.9 Checker Failure

The metrics in the ASM Volumes metric category show information about failures in the alert log checker.

1.9.1 Alert Log Name

This metric shows the name of the alert log.

Target Version	Collection Frequency
11g, 12c	Every 5 minutes

1.9.2 Checker Failure Detected

This metric shows if a failure in the alert log has been detected.

Target Version	Collection Frequency
11g, 12c	Every 5 minutes

1.9.3 Number of Failures

This metric shows the number of failures detected in the alert log.

Target Version	Collection Frequency
11g, 12c	Every 5 minutes

1.10 Cluster Volume Performance

The metrics in the Cluster Volume Performance metric category indicate the performance of the cluster volumes present in an ASM instance.

1.10.1 I/O Response Time

This metric shows the total read errors for the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.2 I/O Per Second

This metric shows I/O per second for the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.3 I/O Size (MB)

This metric shows the I/O size in MB for the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.4 I/O Throughput

This metric shows the I/O throughput for the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.5 Read Errors

This metric shows the total read errors for the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.6 Read Response Time (MS)

This metric shows the total read response time in milliseconds for the volume cluster.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.7 Read Size (MB)

This metric shows the total read size for the volume cluster.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.8 Read Throughput

This metric shows the total read throughput for the volume cluster.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.9 Reads Per Second

This metric shows the reads per second for the volume cluster.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.10 Write Errors

This metric shows the detail of the total number of failed writes for the volume cluster.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.11 Write Response Time (MS)

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

Target Version	Collection Frequency
11gR2, 12c	Every hour

Data Source

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

User Action

No user action is required.

1.10.12 Write Size (MB)

This metric shows the total size of the writes in MB for the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.13 Write Throughput

This metric shows the total write throughput for the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.10.14 Writes Per Second

This metric shows the total size of the writes per second the cluster volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.11 Database Disk Group Usage

Data Source

1.11.1 Total Bytes

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

Target Version	Collection Frequency	Alert Text
10g, 11g, 12c	Every 30 Minutes	Usable total size for Disk Group %dg_name% has fallen to %value% (MB).

Data Source

This metric is calculated by taking the space used by a file using the V$ASM_FILE view and joining it with the V$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.

1.12 Disk Group Imbalance Status

The metrics in the Disk Group Imbalance Status metric category check if any disk groups are out of balance. Under normal operations, ASM automatically rebalances disk groups. These metrics detect conditions where manual rebalances may be required or the power level of a rebalance in progress may need to be raised to give it the necessary resources to complete faster. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.12.1 Actual Imbalance (%)

Actual Imbalance (%) measures the difference in space allocated to the fullest and emptiest disks in the disk group. The comparison is in percent full because 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.

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 minutes

Data Source

This metric is calculated using the following formula:

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.

1.12.2 Actual Minimum Percent Free

The Actual Minimum Percent Free metric 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. Because all allocations are performed 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.

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 minutes

Data Source

The metric is calculated as 100 * (min(FREE_MB / TOTAL_MB)), where FREE_MB and TOTAL_MB are columns in the $ASM_DISK_STAT view.

User Action

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

1.12.3 Disk Count

The Disk Count metric reports the number of disks in the disk group which gives a sense of how widely files can be spread.

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 minutes

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.

1.12.4 Disk Group Percent Imbalance

The Disk Group Percent Imbalance (metric is used to determine if a disk group requires rebalance. Temporary imbalances (caused by a rebalance in progress) are ignored.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 15 Minutes	10	Not Defined	Disk Group %diskGroup% requires rebalance because the space usage imbalance between disks is high.

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

User Action

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

1.12.5 Disk Maximum Used (%) with Rebalance

The Disk Maximum Used (%) with Rebalance metric 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 15 Minutes	Not Defined	95	Increase the rebalance power for Disk Group %diskGroup% because at least one disk is critically low on space.

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 the value of the Disk Maximum Used (%) with Rebalance metric is calculated as (100 - Actual Minimum Percent Free), otherwise the value is 0.

User Action

A critical alert is generated if the value of the Disk Maximum Used (%) with Rebalance metric 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).

1.12.6 Disk Minimum Free (%) without Rebalance

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

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 15 Minutes	20	10	Disk Group %diskGroup% requires rebalance because at least one disk is low on space.

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

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. You should manually initiate a rebalance operation.

1.12.7 Disk Size Variance (%)

The Disk Size Variance (%) metric lists the percentage difference in size between the largest and smallest disks in the disk group. This is 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.

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 Minutes

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.

1.12.8 Rebalance In Progress

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

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 Minutes

Data Source

The value of the Rebalance In Progress metric is retrieved from the operation column of the V$ASM_OPERATION.view

User Action

No user action is required.

1.12.9 Resync In Progress

The Resync In Progress metric returns Yes if a resync operation is in progress, No otherwise.

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 Minutes

1.13 Disk Group Target Component

This configuration metric category collects ASM disk group target component information.

1.13.1 Disk Group Name

This metric shows the disk group target component name.

Target Version	Collection Frequency
10g, 11g, 12c	Every 30 minutes

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.

1.13.2 Disk Count

The Disk Count metric reports the number of disks in the disk group which gives a indication of how widely files can be spread.

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 30 minutes

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.

1.14 Disk Group Usage

The metrics in the Disk Group Usage metric category show the space used by all of the disk groups in the mounted state. These metrics are used to collect information about the disk usage and are used to show the trend of disk group space usage in the application. This information is used to determine the following metrics: Free MB, Total MB, Total Safely Usable MB, Type, Safely Usable File MB, Used %, and Used % of Safely Usable of a disk group for 10g Release 2 and Free MB, Total MB, Type, and Used % for 10g Release 1.

These metrics generate a warning alert if the disk group is 75% used and a critical warning if 90% used. The thresholds for the Disk Group Usage alert should not be fixed at 75% and 90%, because the value depends on the redundancy. In version 10g Release 2, these metrics use 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 yet is able to restore redundancy after disk failure.

Enterprise Manager issues alerts for the following:

• Critical alert when USABLE_FILE_MB <= 0

• Warning alert when USABLE_FILE_MB < 0.1 * REQUIRED_MIRROR_FREE_MB

This metric is collected every 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$ASM_DISKGROUP view for 10g Release 1 and the V$ASM_DISKGROUP_STAT view for 10g Release 2. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.14.1 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10g, 11g, 12c	Every 30 Minutes	Not Defined	Not Defined	Total free size for Disk Group %dg_name% has fallen to %value% (MB).

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 FREE_MB column 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 or deleting existing files in the disk group.

1.14.2 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 30 Minutes	Not Defined	Not Defined	Usable free size for Disk Group %dg_name% has fallen to %value% (MB).

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.

1.14.3 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 30 Minutes	Not Defined	Not Defined	Usable free size for Disk Group %dg_name% has fallen to %value% (MB).

Data Source

This metric value is calculated as follows, using the V$ASM_DISKGROUP_STAT view:

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

It the preceding formula, 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.

1.14.4 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 it is 90% used. The threshold limit can be changed to generate alerts at different values.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10g, 11g, 12c	Every 30 Minutes	75	90	Disk Group %dg_name% is %value%%% used.

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 value is calculated as follows, using 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. You can also remove existing files from the disk group.

1.14.5 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 how redundancy is restored after disk failure.

Target Version	Collection Frequency
10g, 11g, 12c	Every 30 Minutes

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.

1.14.6 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.

Target Version	Collection Frequency
10g, 11g, 12c	Every 30 Minutes

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.

1.14.7 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12cR1	Every 30 Minutes	75	90	Disk group %dg_name% has used %value%%% of safely usable free space (space that can be allocated while still having enough space to recover from failure group failures).

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 calculated from the V$ASM_DISKGROUP_STAT view for 10g Release 2 using the following formula:

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

In this formula, usable_total_mb is derived as follows:
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.

1.15 Disk Path

The metrics in the Disk Path metric category show the disk name and disk path of all the disks. This information is collected at a time interval of 24 hours.

These metrics are collected using data from the V$ASM_DISK view for 10g Release 1 and the V$ASM_DISK_STAT view for 10g Release 2. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.15.1 Disk Name

This metric reports the name of the disk path.

Target Version
10gR2, 11g, 12c

Data Source

The source of this metric is the NAME column in the V$ASM_DISK_STAT and V$ASM_DISK views.

User Action

No user action is required.

1.15.2 Disk Path

This metric is the physical path of the disk.

Target Version
10gR2, 11g, 12c

Data Source

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

User Action

No user action is required.

1.15.3 Group Name

This metric provides the name of the group.

Target Version
10gR2, 11g, 12c

Data Source

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

User Action

No user action is required.

1.16 Disk Status

The metrics in the Disk Status metric category provide disk mode status (offline and online). A critical warning alert is generated if any of the disks are offline.

This metric is collected every 15 minutes. You can change the time limit and threshold limit as required. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.16.1 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
All Versions	Every 15 Minutes	Not Defined	OFFLINE	Disk %dg_name%.%disk_name% is offline.

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 from the GV$ASM_DISK view for 10gRelease 1 and GV$ASM_DISK_STAT view for 10g Release 2.

User Action

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

1.17 Failure Group Imbalance Status

The metrics in the Failure Group Imbalance Status metric category check how even failure group disks are laid out for ASM disk groups. ASM strives for an even distribution of file extents and space usage across all disks in a disk group. It accomplishes this through rebalancing. If the disks are different sizes or the failure groups are different sizes then effective rebalancing cannot be achieved. In this situation, configuration changes are required.

These metrics only apply to disk groups with normal or high redundancy. These metrics will not return data for disk groups with external redundancy, because failure groups are not used in this configuration. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.17.1 Disk Count Imbalance Variance

Failure groups are used to store mirror copies of data: two copies for normal redundancy, three copies for high redundancy. The Disk Count Imbalance Variance metric reports 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 15 Minutes	2	Not Defined	Disk Group %diskGroup% has failure groups with different numbers of disks which may lead to suboptimal space usage. Changing the configuration may alleviate this problem.

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

The value of the Disk Count Imbalance Variance metric 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 is generated when the Disk Count Imbalance Variance value is greater than 1 (the default value). 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.

1.17.2 Disk Size Imbalance (%)

Disk Size Imbalance (%) checks whether 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 15 Minutes	10	Not Defined	Disk Group %diskGroup% has failure groups with disks of different sizes which may lead to suboptimal space usage. Changing the configuration may alleviate this problem.

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

The value of the Disk Size Imbalance metric 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 is generated when the Disk Size Imbalance (%) is greater than 10% (the 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.

1.17.3 Failure Group Count

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

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 Minutes

Data Source

The value of the Failure Group Count metric 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.

1.18 Failure Group Status

The metrics in the Failure Group Status metric category check to see if all of the member disks of any failure group are offline. This is an undesirable condition which risks data loss, because mirror copies of data cannot be stored.

These metrics only apply to disk groups with normal or high redundancy. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.18.1 Available Disks

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

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 Minutes

Data Source

The value of the Available Disks metric 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.

1.18.2 Disk Count for Alerts

The Disk Count for Alerts metric has the same value as Available Disks metric if there is more than one disk in the failure group. If there is exactly one disk in the failure group, the value of Disk Count for Alerts is 1, regardless of whether or not 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 generates a critical alert when a disk goes offline.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10gR2, 11g, 12c	Every 15 Minutes	Not Defined	0	Failure Group %diskGroup%.%failureGroup% is offline.

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

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

User Action

A critical alert is 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.

1.18.3 Disk Count

The Disk Count metric reports the number of disks in the failure group.

Target Version	Collection Frequency
10gR2, 11g, 12c	Every 15 Minutes

Data Source

The value of the Total Disks metric is retrieved from the V$ASM_DISKGROUP_STAT and V$ASM_DISK_STAT views.

User Action

No user action is required.

1.18.4 Online Disk Count for Failure Group with More than 1 Disk

This metric shows the online disk count for failure group with more than one disk.

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 15 minutes

1.19 Instance Disk Performance

The metrics in the Instance Disk Performance metric category indicate the performance of the disks present in an ASM instance. These metrics report the disk performance parameters for all of the disks mounted on an ASM Instance.

These metrics are used to collect information, for example, total I/O and read/write requests, total I/O and read/write time, and the total number of bytes read/written to the disk. These metrics also report the response of the disk for read, write, and I/O throughput. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.19.1 Bytes Read

This metric reports the total number of bytes read from the disk.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.2 Bytes Written

This metric reports the total number of bytes written to the disk.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.3 Last Read Errors

This metric shows the most recent number of read errors for the disk.

Target Version	Collection Frequency
10g, 11g, 12c	Every 15 Minutes

1.19.4 Read Errors

This metric shows the total read errors for the disk.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.5 Read Response Time (MS)

This metric shows the total read response time in milliseconds for the disk.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.6 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, or 0 if set to false.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.7 Write Errors

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

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
10g, 11g, 12cR1	Every 15 Minutes	Not Defined	0	Disk %dg_name%.%disk_name% has %value% Read/Write errors.

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

This metric 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.

1.19.8 Reads

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

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.9 I/O Response Time (MS)

This metric shows the disk response time.

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 15 Minutes

1.19.10 Total I/O Time (MS)

This metric shows the total I/O time in milliseconds.

Target Version	Collection Frequency
10g, 11g, 12cR1	Every 15 Minutes

1.19.11 Write Response Time (MS)

This metric shows the total write response time in milliseconds.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.12 Write Time (MS)

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, or 0 if set to false.

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.19.13 Writes

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

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.20 Instance Disk Group Database Performance

The metrics in the Instance Disk Group Database Performance metric category report the performance of the disk group database present in an ASM instance. These metrics report the disk group database performance parameters for all of the disk groups in an ASM Instance.

1.20.1 Bytes Read

This metric reports the total number of bytes read from the disk group database.

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.20.2 Bytes Written

This metric reports the total number of bytes written to the disks in the database disk group.

Target Version	Collection Frequency
11g 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.20.3 Read Time (MS)

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

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.20.4 Reads

This metric shows the total number of I/O read requests for the disks in the disk group database.

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.20.5 Write Time (MS)

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

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.20.6 Writes

This metric shows the total number of I/O write requests for the disks in the disk group database.

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.21 Instance Disk Group Performance

The metrics in the Instance Disk Group Performance metric category indicate the performance of the disk group present in an ASM instance. These metrics report the disk group performance parameters for all of the disk groups in an ASM Instance.

The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of ASM target type metrics.

1.21.1 Bytes Read

This metric reports the total number of bytes read from the disk.

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.21.2 Bytes Written

This metric reports the total number of bytes written to the disks in the disk group.

Target Version	Collection Frequency
11g 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.21.3 Read Time (MS)

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

Target Version	Collection Frequency
11gR2, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.21.4 Reads

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

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.21.5 Write Time (MS)

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

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.21.6 Writes

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

Target Version	Collection Frequency
11g, 12c	Every 15 Minutes

Data Source

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

User Action

No user action is required.

1.22 Instance Volume Performance

The metrics in the Instance Volume Performance metric category indicate the performance of the instance volumes present in an ASM instance.

1.22.1 I/O Per Second

This metric shows I/O per second for the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.2 I/O Response Time

This metric shows the total read errors for the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.3 I/O Throughput

This metric shows the I/O throughput for the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.4 I/O Size (MB)

This metric shows the I/O size in MB for the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.5 Read Errors

This metric shows the total read errors for the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.6 Read Response Time (MS)

This metric shows the total read response time in milliseconds for the volume instance.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.7 Read Size (MB)

This metric shows the total read size for the volume instance.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.8 Read Throughput

This metric shows the total read throughput for the volume instance.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.9 Reads Per Second

This metric shows the reads per second for the volume instance.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.10 Write Errors

This metric shows the detail of the total number of failed writes for the volume instance.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.11 Write Response Time (MS)

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

Target Version	Collection Frequency
11gR2, 12c	Every hour

Data Source

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

User Action

No user action is required.

1.22.12 Write Size (MB)

This metric shows the total size of the writes in MB for the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.13 Write Throughput

This metric shows the total write throughput for the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.22.14 Writes Per Second

This metric shows the total size of the writes per second the instance volume.

Target Version	Collection Frequency
11gR2, 12c	Every hour

1.23 Offline Disk Count

The metrics in the Offline Disk Count metric category report the number of disks with the mode status offline. The metrics are collected at the cluster level if the target is Cluster ASM. Otherwise, they are collected at the instance level as a part of the ASM target type metrics.

You can change the time limit and threshold limit.

1.23.1 Offline Disk Count

This metric provides the number of disks 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.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
All Versions	Every 15 Minutes	Not Defined	0	%offline_count% disks are offline.

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.

1.24 Response

The Response metric category for Cluster ASM is a repository side metric. It displays whether Cluster ASM is up or down. A Cluster ASM is considered up if any one of the member instances is up and reachable. The check is performed every 5 minutes on each member instance. If the connection is successful on any instance, the status of Cluster ASM is updated as up.

1.24.1 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. An alert is generated for an individual ASM instance that is down.

Target Version	Evaluation and Collection Frequency	Default Warning Threshold	Default Critical Threshold	Alert Text
All Versions	Every 5 Minutes	Not Defined	0	Failed to connect to ASM instance %oraerr%.

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.