Oracle Database Automatic Storage Management (ASM)

Guidance:IT expert network exclusiveOracle Database Automatic Storage Management (ASM)But what is ASM? ASM is an effective abstraction layer that enables your Oracle database to be used together with an abstract space called diskgroups, rather than directly using datafiles. This brings many benefits, but it also requires learning new concepts, commands, usage, and management tasks. So before you invest in your production system, let's look at what it solves, what it manages, and what it looks like. I will introduce it to you one by one.

Why create it?

The best way to answer this question is to directly trace the source, BillBridge-the initial architect of Automatic Storage Management. In OracleASM in the OraclePress title, Bill provides a link where he discussed the problems encountered when managing Oracle data file placement using a file system of a vendor-specific operating system:

1. for archiving logs and backups, the operating system vendor does not provide a shared disk file system.

2. The logical volume manager hides the file location, making it difficult to manage disk I/O and provide good statistics.

3. When the number of disks exceeds 100, the existing lvm cannot work well.

4. When the database has more than 1000 data files, the operating system and Oracle cannot process the database well.

5. It is difficult to name a large number of data files.

6. Features and file system restrictions vary with the operating system.

7. Users at the operating system level can access Oracle files through standard usage, which Oracle does not know.

Therefore, he began to solve these problems by establishing an Oracle file system. His goal is to provide theseFeatures:

1. tightly integrated with Oracle and used with clusters (parallel servers ).

2. automatically use the new storage and manage it as a disk unit or disk group.

3. Supports thousands of disks.

4. The file will not be named and will be hidden in the operating system.

Who needs it?

Now, you can quickly browse the above problems and solutions to help you determine who needs ASM. At first, it was used to process a very large online database. So if it includes your store, you may already be following it, or start executing ASM. If your database is small and there are not many data files, you may need some reason to consider using it.

1. You will be familiar with some new technologies, and should start from building them in your development environment and test them for several months.

2. If you want to get higher performance from your existing Disk Subsystem and get better statistics for predicting disk I/O.

3. If you are using RAC, you need to consider ASM.

The above is the knowledge of Oracle Database Automatic Storage Management (ASM). It is easier to understand this and learn more professional knowledge. These are the basic knowledge of Oracle Database Automatic Storage Management (ASM ,, it is also very important.