AlwaysON – HADRON Learning Series: Worker Pool Usage for HADRON Enabled Databases

I am on several e-mail aliases related to Always On databases (reference Availability Group, AG, HADRON) and the question of worker thread usage is a hot topic this week.  I developed some training around this during the beta so I decided to pull out the relevant details and share them with you all.   Hopefully this…

7

Behavior Change When Handling Character Conversions SQL Server’s ODBC Driver (SQL 2012 – Version 11.xx)

Summary The SQL Server 2012 ODBC Driver (SQLNCLI11.dll) updated handling of SQL_WCHAR* (NCHAR/NVARCHAR/NVARCHAR(MAX)) and SQL_CHAR* (CHAR/VARCHAR/NARCHAR(MAX)) conversions. The change was made to accommodate surrogate pair behavior as outlined at: http://technet.microsoft.com/en-us/library/ms143179(v=SQL.110).aspx   “In versions of SQL Server prior to SQL Server 2012, string functions did not recognize surrogate pairs as a single character. Some string operations…


How It Works: HealthCheckTimeout Interval Activities

As I wrote my recent blog posts and did more research I found that is would be helpful to highlight the HealthCheckTimeout behavior in more detail. Always On FCI (Failover Cluster Instance) vs Non-FCI Installations Documentation The first thing that I need to point out is the subtle wording difference in Books Online and other…

1

How It Works: Failover Cluster/Availability Group XEL Logging Frequency

I had a great question from my post on sp_server_diagnostics (http://blogs.msdn.com/b/psssql/archive/2012/03/08/sql-server-2012-true-black-box-recorder.aspx).  As ‘luck’ would have it, Bob Ward, was working on some training and had a similar question.  As I investigated I uncovered a few details that can help us all. Connection Scope As soon as the Failover Cluster Instance (FCI) or Availability Group is…

2

How It Works: XEvent Action vs Field data values.

I have seen several traces and questions relating to the output of the XEvent so I thought I would try to explain them a bit in an effort to reduce confusion. Terms Field == Event Data Action == Action Data – The action data is gathered from the current session/request state.  Let’s look at the…


AlwaysON – HADRON Learning Series: Automated Failover Behaviors (Denali – Logging History Information, FCI and Default Health Capture, sp_server_diagnostics)

Quite an encompassing title I will agree but the features all work together to build a really nice product.  I had this tucked away during beta and thought it would be helpful to post. SQL Server AlwaysON and "Denali" has undergone a significant upgrade to the way the cluster resource (for an Availability Group or…


SQL Server 2012 – True Black Box Recorder

This would be a perfect time to post a blog talking about the new SQL Server 2012 features.  However, I am going to leave that activity to the marketing folks (AlwaysOn, T-SQL Enhancements, …).   I want to talk about something that might not appear on the top of a marketing or sales checklist but for…

4

Distributed Replay for SQL Server 2012

I recently had a lengthy exchange on DReplay with Jonathan Kehayias (SQL MVP).   From this exchange I filed several work items with the SQL Server development team to help install and setup DReplay easier in the future. Jonathan has started a series of blog posts on his experiences that I would only be copying to…

4