Developer Reference for Intel® oneAPI Math Kernel Library for Fortran

ID 766686
Date 10/31/2024
Public
Document Table of Contents

mkl_disable_fast_mm

Turns off the Intel® oneAPI Math Kernel Library (oneMKL) Memory Allocator for Intel® oneAPI Math Kernel Library (oneMKL) functions to directly use the systemmalloc/free functions.

Syntax

mm = mkl_disable_fast_mm

Fortran Include Files/Modules

  • Include file: mkl.fi
  • Module (compiled): mkl_service.mod
  • Module (source): mkl_service.f90

Description

The mkl_disable_fast_mmfunction turns the Intel® oneAPI Math Kernel Library (oneMKL) Memory Allocator off for Intel® oneAPI Math Kernel Library (oneMKL) functions to directly use the systemmalloc/freefunctions. Intel® oneAPI Math Kernel Library (oneMKL) Memory Allocator uses per-thread memory pools where buffers may be collected for fast reuse. The Memory Allocator is turned on by default for better performance. To turn it off, you can use themkl_disable_fast_mm function or the MKL_DISABLE_FAST_MM environment variable (See the Intel® oneAPI Math Kernel Library (oneMKL) Developer Guide for details.) Call mkl_disable_fast_mmbefore calling any Intel® oneAPI Math Kernel Library (oneMKL) functions that require allocation of memory buffers.

NOTE:

Turning the Memory Allocator off negatively impacts performance of some Intel® oneAPI Math Kernel Library (oneMKL) routines, especially for small problem sizes.

Return Values

Name

Type

Description

mm

INTEGER*4

1 - The Memory Allocator is successfully turned off.

0 - Turning the Memory Allocator off failed.