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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® oneAPI Math Kernel Library Cluster Software
Managing Behavior of the Intel® oneAPI Math Kernel Library with Environment Variables
Configuring Your Integrated Development Environment to Link with Intel® oneAPI Math Kernel Library
Intel® oneAPI 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
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
Overview of the Intel® Distribution for LINPACK* Benchmark
Contents of the Intel® Distribution for LINPACK* Benchmark
Building the Intel® Distribution for LINPACK* Benchmark for a Customized MPI Implementation
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
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Example of Data Alignment
Needs for best performance with Intel® oneAPI Math Kernel Library or for reproducible results from run to run of Intel® oneAPI Math Kernel Library functions require alignment of data arrays. The following example shows how to align an array on 64-byte boundaries. To do this, usemkl_malloc() in place of system provided memory allocators, as shown in the code example below.
Aligning Addresses on 64-byte Boundaries
// ******* C language *******
...
#include <stdlib.h>
#include <mkl.h>
...
void *darray;
int workspace;
// Set value of alignment
int alignment=64;
...
// Allocate aligned workspace
darray = mkl_malloc( sizeof(double)*workspace, alignment );
...
// call the program using oneMKL
mkl_app( darray );
...
// Free workspace
mkl_free( darray );
! ******* Fortran language *******
...
! Set value of alignment
integer alignment
parameter (alignment=64)
...
! Declare oneMKL routines
#ifdef _IA32
integer mkl_malloc
#else
integer*8 mkl_malloc
#endif
external mkl_malloc, mkl_free, mkl_app
...
double precision darray
pointer (p_wrk,darray(1))
integer workspace
...
! Allocate aligned workspace
p_wrk = mkl_malloc( %val(8*workspace), %val(alignment) )
...
! call the program using oneMKL
call mkl_app( darray )
...
! Free workspace
call mkl_free(p_wrk)
Parent topic: Coding Tips