Oracle Installation Guide For High Availability Environment Database

Software Oracle installation and configuration introduces a number of challenges. It its a brand new installation, some of these challenges, such as estimating disk space, laying out the data files, deciding on the Operating system and database block sizes, and determining the maximum number of data files, require making decisions about parameters that are appropriate for your environment. Even before you have had a chance to use your database and find out their appropriateness. The seriousness of making the right decisions intensifies with high availability requirements, where the impact of an improper decision is much more severe because these decisions impose themselves throughout the life of the database. Correcting and improper decision involves long downtime which is seldom tolerated. Installation and configuration are highly critical from a high availability perspective, since they form the foundation upon which all other routine tuning and maintenance tasks operate. At most high availability sites, performance relatively takes a back seat to accessibility, recoverability and maintainability. In their enthusiasm to configure a highly available and maintainable site, however, DBAs sometimes make the database virtually unusable from a performance perspective. This causes major performance audits and corrective action to take place, resulting in downtime and defeating the entire purpose of ignoring performance goals during installation and initial configuration. Rather than focusing solely on availability and causing downtime due to such short sightedness during initial configuration, its always better to look at performance as an equally important objective, at par with recoverability and maintainability. In specific cases where performance objectives directly clash with availability, its advisable to let the latter prevail. So how do DBAs tend to do things right the first time? How can they ever manage to get everything installed and working right out of box? The bad news is, they cant! high availability uptime cannot be achieved merely by doing a vanilla install. It can only be attained by following a combination of good recommendations from Oracle and enhancing those practices based on the DBAs experience in similar environments. But unfortunately, DBA is ignoring Oracle recommendations during installation process of Oracle. After installation process, database wouldnt affect with performance issues but after sometime, some mysterious performance issues are occurring, which are not easily understandable. These all performance issues are presenting wrong selection of basic parameters of Oracle database installation. Take an example, wrong DB_BLOCK_SIZE parameter selection during database installation of data warehousing or DSS database systems. Changing of this parameter needs long downtime because you need re-build database from the scratch. About the Author: 相关的主题文章: