Microsoft Team

SQL Server 2014: buffer pool extension & corruption

I had the opportunity to attend Paul Randal’s session on advanced data recovery techniques at the Pass Summit. During this session one attendee asked Paul if a page that has just been corrupted can remain in the buffer pool extension(…)

SQL Server & memory leak: Are you sure?

I have recently come across an issue with one of my customer that told me that their SQL Server 2008 R2 instance had a memory leak. These are strong words! The server has 64 GB of RAM and the(…)

SQL Server failover cluster, VSphere, & SCSI-3 reservation nightmares

When I have to install a virtualized SQL Server FCI at a customer place as an SQL Server consultant, the virtualized environment usally is ready. I guess this is the same for most part of the database consulting people.

SQL Server: Forced failover with AlwaysOn & Availability Groups

During a workshop at one of my customer about the implementation of SQL Server AlwaysOn and availability groups, I had an interesting discussion. It was about asynchronous replication between 2 replicas and the effect of the forced failover operation(…)

SQL Server 2014: classic commit vs commit with delayed durability & I/Os

When you learn about SQL Server, you will often hear that a commit transaction is a synchronous operation and that you can trust it. In this blog post, I will provide some details about what we mean by synchronous(…)

SQL Server 2014: DBCC CHECKDB and ReFS support

Have you noticed an interesting behavior with SQL Server 2014 when you are running a dbcc checkdb command? If not, you should have a look at this blog post. I discovered it completely by accident during some tests. If(…)

SQL Server: DBCC CHECKDB does not detect corruption

During my audits at customer places, it still happens very often to find SQL Server databases with page verification option configured to “none”. I always alert my customers on this configuration point because it can have an impact on the(…)

SQL Server 2014: sys.dm_exec_query_profiles, a new promising feature

Among the hidden features provided by SQL Server 2014 there is a very interesting dynamic management view named sys.dm_exec_query_profiles. This feature will help the database administrators and experienced developers to troubleshoot long running queries in real-time. I’m pretty sure(…)

SQL Server 2014: Availability groups failover impossible with Failover Cluster Manager

A couple of weeks ago, I worked for a customer that wanted to implement SQL Server 2012 (and not SQL Server 214) AlwaysOn with availability groups. During our tests we performed a bunch of failover tests and the customer(…)

Tempdb enhancements with SQL Server 2014

SQL Server 2014 is definitively designed for performance and I will try to demonstrate it during this blog post. I like to talk about hidden performance features because generally it does not require any changes for applications unlike in-memory(…)