Batch Mode Processing On Rowstore Tables

Dmitry Pilugin shares some thoughts on the expansion of batch mode processing to rowstore tables:

The main advantages of Batch Mode are:

  • Algorithms optimized for the multi-core modern CPUs;
  • Better CPU cache utilization and increased memory throughput;
  • Reduced number of CPU instructions per processed row.

All these features make Batch Mode much faster than Row Mode (typically an order of magnitude, 10x-100x times faster) for analytical queries with CS indexes. One major condition for Batch Mode is a presence of a CS index. If you don’t have a CS index on a table involved in a query, you won’t get Batch Mode.

However, some analytical queries may benefit from Batch Mode without a CS index, or CS cannot be created due to some limitations.

There are a few tricks that allow you to enable Batch Mode on a Rowstore table for example with a dummy filtered CS index (see this post from Itzik Ben-Gan), but SQL Server 2019 may use Batch Mode on Rowstore without any extra efforts from your side.

Dmitry dives into the debugger and teases out the specific circumstances which can help get a query considered for rowstore.  If you want a deep dive into what’s currently available, this is your post.

Related Posts

Load Testing Tools For SQL Server

Brent Ozar shares a list of load testing tools for SQL Server: One thing I need you to understand first: you have to provide the database and the queries. Almost all of the tools in this post, except the last one, are designed to help you run queries, but they don’t include the queries. The […]

Read More

Troubleshooting Spark Performance

Bikas Saha and Mridul Murlidharan explain some of the basics of performance tuning with Apache Spark: Our objective was to build a system that would provide an intuitive insight into Spark jobs that not just provides visibility but also codifies the best practices and deep experience we have gained after years of debugging and optimizing […]

Read More

Categories

October 2018
MTWTFSS
« Sep Nov »
1234567
891011121314
15161718192021
22232425262728
293031