Db2 Tools for z/OS



Db2 Sort - What is it and how does it help? By Denise Tabor

By CALENE JANACEK posted Fri August 07, 2020 02:14 PM


Autonomous, self-driving cars are becoming a reality.  We expect self-driving cars to determine conditions in which to steer, when to accelerate, and when to brake to avoid unexpected obstacles.  This requires an awareness of the environment outside the vehicle as well as monitoring internal systems. Artificial Intelligence (AI) is a key enabling technology driving this new paradigm. 

Much like an autonomous car, IBM Db2 Sort for z/OS uses intelligence to determine how to most efficiently run with your Db2 utilities. When you engage Db2 Sort, it will automatically determine whether there is too much workload on the system to accelerate and it analyzes your internal systems to decide if it makes sense to continue with the performance boost.

While Db2 Sort can improve the performance of sort processing for almost any environment, this improved performance is most impactful for mainframe environments with large volumes of data, large table spaces or large indexes.

Which IBM Db2 for z/OS Utilities?

Db2 Sort will communicate with the IBM Db2 Utilities to intelligently utilize resources in the most efficient manner.

DB2 Sort can accelerate the following IBM Db2 utilities:

  • LOAD

DB2 Sort also improves sort processing for other IBM products such as:

  • Db2 High Performance Unload for z/OS
  • Db2 Recovery Expert for z/OS
  • Db2 Log Analysis Tool for z/OS
How does it work?

Db2 Sort learns from its environment and takes the safest and most efficient actions.  It can make intelligent decisions in a number of areas:

Db2 Sort will analyze the external and internal systems to learn the most efficient way to execute the sort for your DB2 Utility. It is then able to dynamically adjust the resources it needs to provide the best throughput.

Sort processing often involves intensive CPU usage and heavy I/O activity, which in turn requires large amounts of memory and disk space. Db2 Sort is smart enough to determine if the resources exist to increase the number of sorts to run in parallel.

When multiple sorts are run in parallel, Db2 Sort will choose the most efficient and effective use of resources and monitor the execution to adjust the allocation of those resources in order to optimize the use of memory, I/O performance, and CPU processing.

By choosing the most effective use of resources for each sort, Db2 Sort can increase the number of sorts that can be run simultaneously. This can result in lower elapsed time for the application. Db2 Sort will analyze the availability of system memory resources and choose the appropriate amount of memory storage.  It utilizes memory objects and data space to avoid DASD access when possible.  Sort work datasets are used temporarily to facilitate the sorting of an input file that is too large to fit into memory.  By using Db2 Sort, you can optimize and minimize the DASD required to accommodate these work spaces. It will also offload certain processes onto the zIIP processor to decrease the amount of general CPU required to complete the utility execution.

Next Steps?

Db2 Sort will provide greater application availability by executing your sorts in the most efficient way. This can be important when you have batch processing, queries, and updates vying for access to your data while running utilities against your Db2 objects. The ability to monitor and adjust allocations of system resources to optimize CPU processing, I/O performance, and memory usage ultimately reduces internal costs. Db2 Sort analyzes the environment it is running in and the internal systems at its disposal in order to most efficiently sort your data during utility execution.

How can you determine if your Db2 environment will benefit from using Db2 Sort to improve performance and reduce costs?  Your IBM technical product specialist can discuss your utilities environment and suggest the IBM Db2 Utilities Sort Report for z/OS (DUSAR).  DUSAR can help demonstrate the value of Db2 Sort by reporting on the amount of sort time spent in IBM Db2 Utilities.  DUSAR collect information on the amount of utility sort, the amount of CPU and zIIP usage being done in your Db2 Utilities environment.  There is no charge for DUSAR. (Click here for DUSAR.) If you have an IBMid, you should be able to download DUSAR. Contact your IBM technical product specialist for assistance or questions on DUSAR and Db2 Sort for z/OS.