Developer Guide
Developer Guide for Intel® oneAPI Math Kernel Library Windows*
ID
766692
Date
6/30/2025
Public
Getting Help and Support
What's New
Notational Conventions
Related Information
Getting Started
Structure of the Intel® oneAPI Math Kernel Library
Linking Your Application with the Intel® oneAPI Math Kernel Library
Managing Performance and Memory
Language-Specific Usage Options
Obtaining Numerically Reproducible Results
Coding Tips
Managing Output
Working with the Intel® Math Kernel Library Cluster Edition Software
Managing Behavior of the Intel® oneAPI Math Kernel Library with Environment Variables
Programming with Intel® Math Kernel Library in Integrated Development Environments (IDE)
Intel® Math Kernel Library Benchmarks
Appendix A: Intel® oneAPI Math Kernel Library Language Interfaces Support
Appendix B: Support for Third-Party Interfaces
Appendix C: Directory Structure in Detail
Notices and Disclaimers
Using the /Qmkl Compiler Option
Using the /Qmkl-ilp64 Compiler Option
Automatically Linking a Project in the Visual Studio* Integrated Development Environment with Intel® oneAPI Math Kernel Library
Using the Single Dynamic Library
Selecting Libraries to Link with
Using the Link-line Advisor
Using the Command-Line Link Tool
OpenMP* Threaded Functions and Problems
Functions Threaded with Intel® Threading Building Blocks
Avoiding Conflicts in the Execution Environment
Techniques to Set the Number of Threads
Setting the Number of Threads Using an OpenMP* Environment Variable
Changing the Number of OpenMP* Threads at Run Time
Using Additional Threading Control
Calling oneMKL Functions from Multi-threaded Applications
Using Intel® Hyper-Threading Technology
Managing Multi-core Performance
Managing Performance with Heterogeneous Cores
Message-Passing Interface Support
Linking with Intel® Math Kernel Library Cluster Edition Software
Determining the Number of OpenMP* Threads
Using DLLs
Setting Environment Variables on a Cluster
Interaction with the Message-Passing Interface
Using a Custom Message-Passing Interface
Examples of Linking for Clusters
Overview of the Intel® Distribution for LINPACK* Benchmark
Contents of the Intel® Distribution for LINPACK* Benchmark
Building the Intel® Distribution for LINPACK* Benchmark
Building the Netlib HPL from Source Code
Configuring Parameters
Ease-of-use Command-Line Parameters
Running the Intel® Distribution for LINPACK* Benchmark
Heterogeneous Support in the Intel® Distribution for LINPACK* Benchmark
Environment Variables
Improving Performance of Your Cluster
Setting the Environment Variables for Threading Control
To set the environment variables used for threading control, in the command shell in which the program is going to run, enter:
set <VARIABLE NAME>=<value>
For example:
set MKL_NUM_THREADS=4
set MKL_DOMAIN_NUM_THREADS="MKL_DOMAIN_ALL=1, MKL_DOMAIN_BLAS=4"
set MKL_DYNAMIC=FALSE
set MKL_NUM_STRIPES=4
Some shells require the variable and its value to be exported:
export <VARIABLE NAME>=<value>
For example:
export MKL_NUM_THREADS=4
export MKL_DOMAIN_NUM_THREADS="MKL_DOMAIN_ALL=1, MKL_DOMAIN_BLAS=4"
export MKL_DYNAMIC=FALSE
export MKL_NUM_STRIPES=4
Alternatively, you can assign values to the environment variables using Microsoft Windows* OS Control Panel.
Parent topic: Using Additional Threading Control