What is ASM striping in Oracle?

What is ASM striping in Oracle?

ASM striping is the process of dividing a file into 1 MB extents and spreading the extents evenly across all disks in the disk group. An extent is a specific number of contiguous data blocks, obtained in a single allocation, used to store a specific type of information.

What is mirroring in ASM?

It means that every stripe is mirrored once. There is a primary on one disk and a mirror on another disk. Mirroring protects data integrity by storing copies of data on multiple disks. Failure groups are used to place mirrored copies of data so that each copy is on a disk in a different failure group.

What is ASM template?

Templates are collections of attribute values that are used to specify disk regions, file mirroring, and striping attributes for an Oracle ASM file when it is created.

What is AU size in ASM?

The Allocation Unit or AU size is the smallest amount of storage that may be allocated to or removed from an ASM diskgroup.

What is Diskgroup in ASM?

ASM Diskgroups. The main components of ASM are diskgroups, each of which comprise of several physical disks that are controlled as a single unit. The physical disks are known as ASM disks, while the files that reside on the disks are known as ASM files.

What are the advantages of ASM?

ASM provides the following benefits: Striping—ASM spreads data evenly across all disks in a disk group to optimize performance and utilization. This even distribution of database files eliminates the need for regular monitoring and I/O performance tuning.

What is Lun in Oracle ASM?

Logical Unit Number (LUN) A LUN is a disk presented to a computer system by a storage array. Oracle recommends that you use hardware RAID functionality to create LUNs. Storage hardware RAID 0+1 or RAID5, and other RAID configurations, can be provided to Oracle ASM as Oracle ASM disks.

Where is allocation unit in ASM?

June 16, 2013

  1. This post is about the amount of space allocated to ASM based files.
  2. SQL> select NAME, GROUP_NUMBER, ALLOCATION_UNIT_SIZE/1024/1024 “AU size (MB)”, TYPE.
  3. SQL> create tablespace T1 datafile ‘+DATA’ size 10 M;
  4. Get the ASM file numbers for those two files:

What is rebalance power in ASM?

Whenever there is a disk added/removed/resized, ASM starts to rebalance the data on the disks in the disk group. The power with which it does the rebalancing is the rebalancing power. The rebalance power defaults to the value of the ASM_POWER_LIMIT initialization parameter (default value = 1).

What is normal redundancy in ASM?

Normal redundancy. Oracle ASM provides two-way mirroring by default, which means that all files are mirrored so that there are two copies of every extent. A loss of one Oracle ASM disk is tolerated. You can optionally choose three-way or unprotected mirroring.