The Lazywriter

The purpose of the lazywriter is twofold: (1) to keep a specified number of BPool buffers free so they can be allocated for use by the server and (2) to monitor and adjust the committed memory usage by the BPool so that enough physical memory remains free on the system to prevent Windows from paging (provided dynamic memory management is enabled so that the lazywriter can adjust the size of the BPool as necessary). SQL Server estimates the number of BPool buffers to keep free based on the system load and the number of stalls occurring (the number of times a memory consumer within the server has to wait on a free buffer page).

The amount of physical memory the lazywriter attempts to keep free usually varies between 4MB and 10MB. ...

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