SQL Server2008 Resource Governor简介
Introduction to the SQL Server 2008 Resource Governor
Database Administration, Performance Tuning | January 4, 2010 | 4:05 pm
This is an excerpt from my free eBook, Brad’s Sure Guide to SQL Server 2008.
I think most of us are familiar with this situation: a SQL Server database is the backend of an OLTP (Online Transaction Processing) application, but you are required to allow users to run any reports they want on the production data, any time they want. This often results in long-running reports that negatively affect OLTP performance. Haven’t you ever wished you could limit the amount of hardware resources allocated to reporting, so that normal production activity is not affected?
In SQL Server 2008, you can. The Resource Governor, available only in the Enterprise Edition of SQL Server 2008, is a technology that allows you to selectively control how much CPU and memory resources are assigned to a particular workload. For example, the Resource Governor allows you to specify that no more than 20% (or any figure you designate) of CPU and/or memory resources can be allocated to running reports. When this option is turned on, then no matter how many reports are run, they can never exceed their designated resource allocation. Of course, this will reduce the performance of reporting, but at least now production OLTP activity won’t be as negatively affected by reports.
Currently, Resource Governor only works within the database engine. It does not work with Integration Services, Reporting Services, or Analysis Services.
In this chapter you will learn how you can use the Resource Governor to better prioritize and manage a SQL Server’s workload, how Resource Governor works under the hood, and how to configure it for use.
Uses for Resource Governor
Resource Governor is designed to help DBAs four different ways:
Managing Unpredictable Workloads
As in my reporting example above, it is often difficult to know how your SQL Server resources are
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