Is the average wait time for SQL too high?
Recently we started to receive many alerts from SCOM : Alert: SQL 2008 DB Average Wait Time is too high. When reviewed the graph for this counter, we found that the alert is always ranging between 1,000 (ms) and 2,500 (ms) . is there a specific way\\query that can identify which queries are causing this locking which lead to the high wait time ?
How long does it take to get a lock in SQL Server?
Total wait time (in milliseconds) for locks in the last second. Number of lock requests per second that required the caller to wait. Number of lock requests per second that resulted in a deadlock.
How to calculate lock timeout in SQL Server?
Number of new locks and lock conversions per second requested from the lock manager. Lock Timeouts (timeout > 0)/sec. Number of lock requests per second that timed out, but excluding requests for NOWAIT locks. Lock Timeouts/sec. Number of lock requests per second that timed out, including requests for NOWAIT locks.
How to know if SQL Server is waiting on something?
Look at wait stats, which tracks what your SQL Server has been waiting on. My personal favorite tool for that is sp_Blitz @CheckServerInfo = 1, @OutputType = ‘markdown’ because you can post the results here on Stack in your question. (Disclaimer: I work for the company that started those scripts.)
Which is the query with the most waits?
Top query is the query that had most waits. This is only for queries that are still cached.
How to find the longest running queries in SQL?
You can use the @SortOrder parameter to look for queries either with the most total duration accumulated in your plan cache: That will average our duration over executions to find the longest running by average. You’ll get back a ton of information about each query, including the query plan.
How much memory does a SQL Server need?
Server has 80GB memory, 64GB allocated to SQL Server standard edition and an external DAS box with two RAID10 arrays, each 12 disks, one for tempdb and another for customer databases. SQL database log files go to an internal RAID5 array with 6 disks and OS and swap is on a RAID1 array. CPUs are dual 6 core X5690s at 3.4GHz.
How to determine which query took a lock?
This example demonstrates a method of determining what query took the lock, the plan of the query, and the Transact-SQL stack at the time the lock was taken. This example also illustrates how the pairing target is used in an Extended Events session.