tailieunhanh - The Real MTCS SQL Server 2008 Exam 70/432 Prep Kit- P124

The Real MTCS SQL Server 2008 Exam 70/432 Prep Kit- P124: Congratulations on your journey to become certified in SQL Server 2008. This book will help prepare you for your exam and give you a practical view of working with SQL Server 2008. | Performance Tuning Chapter 13 597 customers realizing many benefits of better hardware utilization and more costeffective database deployments. However consolidation does have some drawbacks. The most common objections to server consolidation is performance because shared multi-instance servers and shared SQL Server instances can introduce challenges in ensuring consistent performance for all database users. Common problems arise from mixed users where regular OnLine Transaction Processing OLTP users mix with reporting users on the same instance examples can be found where databases for the finance department combine with sales order databases. In this situation normal database traffic consisting of inserts updates and deletes can conflict with the workload generated by reports run by finance users executing month- or year-end reports based on historic sales data. The Resource Governor was introduced to SQL Server 2008 to provide predictable performance for mission-critical workloads. Resource Governor achieves predictable performance by monitoring and reserving minimum levels of critical resources such as CPU and memory for specific tasks or groups of tasks. Resource Governor Concepts The Resource Governor consists of three key concepts Resource Pools Workload Groups and Classification Functions. The Resource Governor exists to manage minimum resources available for different groups of users or tasks. However the governor is more intelligent than simply dividing resources among users if resources are unused elsewhere on a server a given user can be permitted to use excess of their quota up to a maximum allocation until a time when another user or process requires the resource memory or CPU . This section introduces each concept and uses an example to illustrate the purpose and implementation of the concept. The example relates to a college whereby requests from lecturers should receive priority over requests received from students. Resource Pools Resource pools .