Wait Statistics in Azure SQL Database

Azure, TSQL
You need to be aware that you're going to see differences when you're working with Azure SQL Database when it comes to wait statistics. If you're running a v12 Azure SQL Database (and if you're not, go fix it), you can run a query against sys.dm_os_wait_stats. Here's the output for the TOP 10 waits ordered by wait time on one of my databases: Everything you're used to seeing, right? Well... not quite. This is Azure SQL Database. So, let's use sys.dm_db_wait_stats, a DMO that is only available within Azure. This lists waits by database. The TOP 10 here are: You'll notice that these results are wildly different from those above. What we're looking is largely a server versus a database, but not completely. I mean that sys.dm_os_wait_stats is showing the waits for the…
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Why Is The Server Slow?

SQL Server 2005, SQL Server 2008, SQL Server 2012, SQL Server 2014, SQL Server 2016, TSQL
This is blog post #2 in support of Tim Ford's (b|t) #iwanttohelp, #entrylevel. If you haven't been working in SQL Server for very long, you may not have got this phone call yet, but you will: Hi, yeah, the server is slow. Thanks. Bye. Let's pretend for a moment that you know which server they're referring to (because just finding out that piece of information can be a challenge). Now what? The list of tools and mechanisms within SQL Server for gathering metrics is extremely long: Performance Monitor Dynamic Management Views & Functions System Views Extended Events Trace Events Activity Monitor Data Collector Execution Plans 3rd Party Tools I'm leaving out lots of stuff in that list. So where do you start when you get this phone call? Where is the server slow?…
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