New SQL Server 2016 functionality helps SAP supportability

Due to the combined effort of the SAP – Microsoft Porting group the SQL Server Development team added a new functionality to the SQL Server UPDATE STATISTICS command and to the way SQL Server automatically updates statistics. This new functionality enables the SAP customers on SQL Server to persist a sample rate of the manual… Read more

Moving from SAP 2-Tier to 3-Tier configuration and performance seems worse

Lately we were involved in a case where a customer moved a SAP ERP system from a 2-Tier configuration to a 3-Tier configuration in virtualized environments. This was done because the customer virtualized the system and could not provide VMs large enough on the new host hardware to continue with a 2-Tier SAP setup. Hence… Read more

SQL Server has encountered I/O requests taking longer than 15 seconds

Most of us have seen these errors in the SQL Server error log pointing to a IO subsystem problem: 2015/06/15 12:43:01 spid8s SQL Server has encountered 1016 occurrence(s) of I/O requests taking longer than 15 seconds to complete on file [N:\ABCDATA8\ [ABCDATA8.ndf] in database [ABC] (5). The OS file handle is 0x000000000000172C.  The offset of the… Read more

Data distribution and SQL Plans

For customers of SAP (and others) it is very important that the runtime of the different reports or programs is predictable, fast and stable. From time to time it happens that former fast query executions deteriorate in their runtime and need much more time than before. For most of the customers it is totally unclear… Read more

Deadlock Analysis (Advanced)

With this blog my small deadlock serie will be completed. We started with the basics, then we discussed several examples and today we will close up with a more advanced approach to solve deadlocks. The intention to build this solution was to get the complete transactions that led to the deadlock, as in some cases… Read more

Deadlock Analysis (Examples)

As promised in my former blog about Deadlock Analysis we proceed today with the deadlock serie with examples and their solutions. Update Locks The first example is a Deadlock with two identical statements, doing deletes on table BC_MON_AGREGATES: The statements are: DELETE FROM BC_MON_AGREGATES WHERE AGR_INTERVAL = @P0 AND START_TIME < @P1; As you can… Read more

Deadlock Analysis (Basic)

Today I want to start a small blog series for the deadlock analysis with SQL Server. In the first part we will cover the basics about deadlocks, why and when they occur and how to capture them. The second part which will be more exciting will cover the basic analysis of deadlocks and the different… Read more

Extended Events with SAP (Part I)

Here is another great contribution by Clas Hortien in regards to new technologies which got introduced in SQL Server 2008. Clas will continue in this series around XEvents and new technologies. This blog will briefly discuss how the possibilities of the new tracing functionality of Extended Events can be used for the problem analysis within an… Read more