This rule checks that lightweight pooling is disabled on the server. Setting lightweightpooling to 1 causes SQL Server to switch to fiber mode scheduling. Fiber mode is intended for certain situations in which the context switching of the UMS workers is the important bottleneck in performance. Because this is rare, fiber mode seldom improves performance or scalability on the typical system. Improved context switching in Microsoft has also reduced the need for fiber mode.
Best Practices Recommendations
The lightweightpooling option should only be enabled after thorough testing, after all other performance tuning opportunities are evaluated, and when context switching is a known issue in your environment.
We recommend that you do not use fiber mode scheduling for routine operation because it can decrease performance by preventing the regular benefits of context switching, and because some components of SQL Server that use Thread Local Storage (TLS) or thread-owned objects, such as mutexes (a kind of Win32 kernel object), cannot function correctly in fiber mode
To remove lightweight pooling, execute the following statement, and then restart the SQL Server Database Engine.
sp_configure 'show advanced options', 1;
GO
sp_configure 'lightweightpooling', 0;
GO
RECONFIGURE;
GO
lightweight pooling Option
Concepts
Monitoring and Enforcing Best Practices by Using Policy-Based Management
Help and Information
Getting SQL Server 2008 Assistance