ASM INSTANCE

Initialization Parameters for ASM Instances

The following initialization parameters relate to an ASM instance. Parameters that start with ASM_ cannot be set in database instances.

Name	Description
INSTANCE_TYPE	Must be set to ASM Note: This is the only required parameter. All other parameters take suitable defaults for most environments.
ASM_POWER_LIMIT	The default power for disk rebalancing. Default: 1, Range: 0 – 11
ASM_DISKSTRING	A comma-separated list of strings that limits the set of disks that ASM discovers. May include wildcard characters. Only disks that match one of the strings are discovered. String format depends on the ASM library in use and on the operating system. The standard system library for ASM supports glob pattern matching. For example, on a Solaris server that does not use ASMLib, to limit discovery to disks that are in the /dev/rdsk/ directory, ASM_DISKSTRING would be set to: /dev/rdsk/* another example: /dev/rdsk/s3,/dev/rdsk/s4 (This could be simplified to:) /dev/rdsk/*s[34] Default: NULL. A NULL value causes ASM to search a default path for all disks in the system to which the ASM instance has read/write access. The default search path is platform-specific.
ASM_DISKGROUPS	A list of the names of disk groups to be mounted by an ASM instance at startup, or when the ALTER DISKGROUP ALL MOUNT statement is used. Default: NULL (If this parameter is not specified, then no disk groups are mounted.) This parameter is dynamic, and if you are using a server parameter file (SPFILE), you should not need to manually alter this value. ASM automatically adds a disk group to this parameter when the disk group is successfully created or mounted, and automatically removes a disk group from this parameter when the disk group is dropped or dismounted.

ASM Instance Memory Requirements

ASM instances are smaller than database instances. A 64 MB SGA should be sufficient for all but the largest ASM installations. Total memory footprint for a typical ASM instance is approximately 100 MB.