The only exception to this is if you use the
Chapter 4: Physical Database Layouts and Storage Management 103
shutdown abort command on the ASM instance, which eventually forces all dependent databases
to perform a shutdown abort.
For multiple ASM instances sharing disk groups, such as in a Real Application Clusters (RAC)
environment, the failure of an ASM instance does not cause the database instances to fail. Instead,
another ASM instance performs a recovery operation for the failed instance.
ASM Dynamic Performance Views
A few new dynamic performance views are associated with ASM instances. Table 4-3 contains
the common ASM-related dynamic performance views. We??™ll provide further explanation, where
appropriate, later in this chapter for some of these views.
ASM Filename Formats
All ASM files are Oracle-Managed Files (OMF), so the details of the actual filename within the
disk group is not needed for most administrative functions. When an object in an ASM disk group
is dropped, the file is automatically deleted. Certain commands will expose the actual filenames,
such as alter database backup controlfile to trace, as well as some data dictionary and dynamic
View Name Used in Standard
Database?
Description
V$ASM_DISK Yes One row for each disk discovered by an ASM
instance, used by a disk group or not. For
a database instance, one row for each disk
group in use by the instance.
V$ASM_DISKGROUP Yes For an ASM instance, one row for each disk
group containing general characteristics of the
disk group.
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