IV70448: UNABLE TO ALLOCATED GREATER THAN 256M OF MEMORY WITH OMP_STACKSIZE

XL C/C++ for AIX Fix Pack 3 (April 2015 PTF) for 13.1
XL C/C++ Runtime for AIX Fix Pack 2 (April 2015 PTF) for 13.1
XL C/C++ for AIX Fix Pack 4 (July 2015 PTF) for 13.1
XL C/C++ Runtime for AIX Fix Pack 3 (July 2015 PTF) for 13.1
XL Fortran for AIX Fix Pack 4 (July 2015 PTF) for 15.1
XL Fortran Runtime for AIX Fix Pack 4 (July 2015 PTF) for 15.1
XL C/C++ for AIX Fix Pack 5 (November 2015 PTF) for 13.1
XL C/C++ Runtime for AIX Fix Pack 4 (November 2015 PTF) for 13.1
XL C/C++ for AIX Fix Pack 6 (February 2016 PTF) for 13.1
XL C/C++ Runtime for AIX Fix Pack 5 (February 2016 PTF) for 13.1
XL Fortran for AIX Fix Pack 6 (February 2016 Update) for 15.1
XL Fortran Runtime for AIX Fix Pack 6 (February 2016 PTF) for 15.1
XL C/C++ for AIX Fix Pack 7 (May 2016 PTF) for 13.1
XL Fortran for AIX Fix Pack 7 (May 2016 Update) for 15.1
XL Fortran Runtime for AIX Fix Pack 7 (May 2016 PTF) for 15.1
XL C/C++ for AIX Fix Pack 8 (August 2016 PTF) for 13.1
XL Fortran for AIX Fix Pack 8 (August 2016 Update) for 15.1
XL Fortran Runtime for AIX Fix Pack 8 (August 2016 PTF) for 15.1
XL C/C++ for AIX Fix Pack 9 (June 2017 PTF) for 13.1
XL Fortran for AIX Fix Pack 9 (June 2017 Update) for 15.1
XL Fortran Runtime for AIX Fix Pack 9 (June 2017 PTF) for 15.1
XL C/C++ for AIX Fix Pack 10 (February 2018 PTF) for 13.1
XL Fortran for AIX Fix Pack 10 (February 2018 PTF) for 15.1
XL Fortran Runtime for AIX Fix Pack 10 (February 2018 PTF) for 15.1
XL Fortran for AIX Fix Pack 3 (April 2015 PTF) for 15.1
XL Fortran Runtime for AIX Fix Pack 3 (April 2015 PTF) for 15.1
XL Fortran for AIX Fix Pack 5 (November 2015 Update) for 15.1
XL Fortran Runtime for AIX Fix Pack 5 (November 2015 PTF) for 15.1
XL C/C++ for AIX Fix Pack 11 (November 2018 PTF) for 13.1

APAR status

• Closed as program error.

Error description

• Attempting to set the OMP_STACKSIZE environment variable to a
  memory size greater than 256 megabytes fails.
  
  
  === TEST CASE ===
  
  #include <stdio.h>
  #include <omp.h>
  
  int main()
  {
   #pragma omp parallel
   {
    char p;
    printf("%d 0x%p\n", omp_get_thread_num(), &p);
    }
  }
  
  
  
  $ xlc_r -qsmp -q64 test.c
  $ export OMP_STACKSIZE=256M
  $ ./a.out
  0 0xfffffffffffe1d0
  2 0x130021660
  1 0x120015660
  $ export OMP_STACKSIZE=257M
  $ ./a.out
  1587-101 Error encountered while attempting to allocate a data
  object.  The program will stop.
  $
  

Local fix

Problem summary

• PROBLEM DESCRIPTION:
  The XLSMP runtime is unable to allocate memory sizes larger
  than 256MB.
  
  USERS AFFECTED:
  Users setting OMP_STACKSIZE to larger than 256MB.
  

Problem conclusion

• Fix was implemented.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  XL SMP AIX

• Fixed component ID

  5725C7401

Applicable component levels

• R410 PSY

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