When and Where to Use ASM


Automatic Storage Management is useful in environments with large databases and frequent increases in data volumes. Some examples of constantly increasing data volumes would be credit-card and banking applications, retail environments, cellular and telephone carriers, travel reservations, security applications, and the like, where the data needs to be preserved for a longer time due to regulatory and other business reasons.

ASM provides a centralized storage-management solution for Oracle databases. The deployment of ASM will be a stepping-stone for grid deployment, lower manageability costs, and higher availability of disk resources. It also simplifies migration to new storage hardware, reduces the number of devices to be managed, and reduces the overall complexity. ASM eliminates the need for I/O tuning and also avoids hotspots at the file-system level.

ASM provides clustered volume manager and file system functionality directly to the database and bypasses the need for third-party clustering software. It also helps to protect against storage array failures.

As in any other new technology, your organization should test smaller databases on the ASM storage and gain experience before doing a full-fledged conversion of all systems to ASM. The technology will mature and be even simpler to use in years to come and with coming releases of Oracle products. In future, ASM could replace all vendor products for database storage management.

ASM Improvements in Oracle Database 10g Release 2

We have already reviewed the WAIT option in conjunction with our discussion of the REBALANCE operation. Oracle Database 10g Release 2 offers an ASM command-line interface (ASMCMD) utility to access and manage files from a command prompt. ASM/XDB FTP support is another new feature that allows the use of XDB and ASM with a user interface for getting files into and out of ASM-managed storage.

Release 2 also expands the ASM capabilities to support multiple Oracle database versions and multiple database-to-ASM connection types. When multiple Oracle database versions are used, ASM utilizes the functionality of the lowest available version. For this purpose, two new columnsSOFTWARE_VERSION and COMPATIBLE_VERSIONhave been added to V$ASM_CLIENT.

ASM allows batch selection of multiple disks for operations like check, delete, and resize. This prevents the unnecessary rebalancing that occurs when disks are deleted one by one and improves usability of the disks by the database.



    Oracle Database 10g Insider Solutions
    SUSE LINUX Enterprise Server 9 Administrators Handbook
    ISBN: 672327910
    EAN: 2147483647
    Year: 2006
    Pages: 214

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