SQL Server According to Bob

Two guys who work on SQL Server

Month: July 2016

How It Works: Reader / Writer Synchronization

This post is not about a specific SQL Server object but instead outlines a technique used in various locations to reduce contention while still providing thread synchronization.  There are hundreds of locations throughout the SQL Server code base that must account for multi-threaded access.   A common technique used in multi-threaded coding is a reader, writer […]

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The SQL Server Basic Installer: Just Install It!

20+ years ago when I joined Microsoft I was handed a diskette (maybe it was two), and was told “Here is SQL Server. Go install it”. So I proceeded to install SQL Server 4.20 on my Windows NT 3.1 desktop machine (I won’t tell you the hardware details. It would scare you). There was a […]

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DBCC Trace Flags 2562 and 2549

  Erin Stellato and Jonathan Kehayias from sqlskills reached out asking for clarification of trace flags 2562 and 2549 behavior.  Trace flags 2562 and 2549 are documented in knowledgebase article: https://support.microsoft.com/en-us/kb/2634571 and the blog post https://blogs.msdn.microsoft.com/bobsql/2016/06/03/sql-2016-it-just-runs-faster-dbcc-scales-7x-better/ highlights the SQL 2016 DBCC performance improvements. For SQL Server 2008, 2012 and 2014 the trace flag behavior remains […]

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How it Works: XEL Health Session and Shutdown

  There are a variety of posts talking about the black box recorder (XEL Health Session) explaining what the recorder is and does: https://blogs.msdn.microsoft.com/psssql/2012/03/08/sql-server-2012-true-black-box-recorder/ This week I ran into niche behavior while looking at the health session output.  While it is unlikely to have any impact on your server the output during a SQL Server […]

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