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"To say I like SP_WhoIsActive is an understatement. This is probably the most useful and effective stored procedure I've ever encountered for activity monitoring. The purpose of the SP_WhoIsActive stored procedure is to give DBAs and developers as much performance and workload data about SQL Server's internal workings as possible, while retaining both flexibility and security. It was written by Boston-area consultant and writer Adam Machanic, who is also a long-time SQL Server MVP, a founder of SQLBlog.com, and one of the most elite individuals who are qualified to teach the Microsoft Certified Master classes."

"Recently I encountered a case when I knew much more about the data than the optimizer. Originally the performance was horrible, this is why I had to have a look at the query in the first place. When I was able to share my knowledge with the optimizer, it produced a better plan, and the query ran dramatically faster."

"Microsoft SQL Server performs dynamic memory management based on the memory requirements of the current load and activities on the system. On a Windows Server 2003 or a Windows XP or later version system, SQL Server can use the memory notification mechanisms that are provided by the QueryMemoryResourceNotification Windows API. On a Microsoft Windows 2000 Server-based system, SQL Server periodically calculates the free physical memory on the system by using the native Windows API. Based on this information from the QueryMemoryResourceNotification Windows API or from the memory calculation, SQL Server responds to the current memory situation on a specific system. This provides the following benefits:"

"As part of my talk at the 2009 US PASS Summit here in Seattle called Inside SQL Server Wait Types, I'm creating this blog post as a reference point that can be used to find out information about wait types in SQL Server 2005 and 2008. My hope is that if you have a question about a wait type you encounter with SQL Server 2005, 2008, or beyond, you will use this blog post as the starting point. This blog post should also be used as an enhancement to what you can find at the following SQL Server Books Online topic:"

"There can be a great difference in the performance of a particular routine in a test database, and in a fully loaded production system. When you hit performance problems in a database under load, and there is excessive locking and blocking, how can you determine exactly where the problems lie, in order to fix them? Read on..."

"Lock escalation is a event which occurs when SQL Server decides to upgrade a lock at a lower level hierarchy to a lock to a table level lock., In other words, when a particular query obtains a large number of row level locks/ page level locks, SQL Server decides that instead of creating and granting number of row level/page level locks, it is effective to grant a single table level lock. Or to be precise,"