Memory Performance Analysis
A system can directly impact SQL Server and the queries running on it in three primary places: memory, disk, and CPU. You’re going to explore each of these in turn starting, in this chapter, with memory. Queries retrieving data in SQL Server must first load that data into memory. Any changes to data are first loaded into memory where the modifications are made, prior to writing them to disk. Many other operations take advantage of the speed of memory in the system, from sorting data due to an ORDER BY clause in a query to performing calculations to create hash tables for joining two tables. Because of all this work being done within the memory of the system, it’s important that you understand how memory is being managed.