The Windows power plan decides how fast the processors run, and an energy saving plan can slow SQL Server without raising any error. This post shows how to check the active plan, how to switch it and undo the change, and how to time the difference with a repeatable T-SQL loop.
Signal Waits: Detect CPU Pressure With Wait Statistics
Signal waits are the part of every wait that a task spends in the queue for a free CPU. This post ranks the wait types by signal time, shows why timer waits ruin the total share, and samples the signal share into a small table so a whole working day can be read interval by interval.
How to Skip Top N Rows in SQL Server? – Interview Question of the Week #237
Question: How to skip top N Rows in SQL Server and retrieve the rest of the rows? Answer: I had asked the above question in one of the interviews last week.
SQL SERVER – Patch Install Rule Error – Not Clustered or the Cluster Service is Up and Online
The error which we observed was a failure of a rule – Patch Install Rule Error – Not clustered or the cluster service is up and online.
THREADPOOL Waits: When Raising Max Worker Count Helps
THREADPOOL waits mean tasks waited for a worker thread. Five read-only queries separate real thread starvation from blocking and busy CPUs. The post lists five signs and shows how to raise the cap in small steps.
Delete the Wrong Row: A Cheap Answer That Passes the Test
A cheap answer to the multiple table delete puzzle reads only 6 pages and passes the check. It can still delete the wrong row. This post shows the answer, asks you to find the row it removes by mistake, and fixes it with a delete that costs 5 reads.
Max Worker Count: Why Typing 10000 Slowed a Server
Max worker count looks like a speed dial but behaves like a safety limit. A client typed 10000 on an 8 processor server and slowed it, and a reset to 0 fixed it in minutes. Two read-only queries show your value and whether workers run short.