[Omp] Error: The PPD directives stack limit has been exceeded.

[Faustin Roman]

Hi everyone!

I get this message when trying to compile a fortran code with Intel
Fortran v.9.0.021:

fortcom: Error: mpi_prog.for, line 315: The PPD directives stack limit
has been exceeded.

Please tell me if I should increase the stack limit (currently at 8192) or the
KMP_SET_STACKSIZE_S()

I have tried both ways but nothing seems to work...

(I don't know if the version of glibc is built with the
FLOATING_STACKS parameter defined
as required by Intel workaround - see below)

Any ideeas?

Thanks,
Faustin Roman

PS: If it helps someone, here is what I found so far...

Intel(r) Fortran Compiler 9.0 for Linux Release Notes:

"OpenMP Limitations

POSIX threaded programs that require a large stack size may not run
correctly on some versions of Linux because of hard-coded stack size
limits in some versions of the Linux POSIX threads libraries. These
limits also apply to OpenMP programs (-openmp) and automatically
generated parallel programs (-parallel) with the Intel compilers,
because the Intel compilers use the POSIX threads library to implement
OpenMP based and automatically generated parallelism. Threaded
programs that exceed the stack space limit usually experience
segmentation violations or addressing errors.

To avoid these limitations, use a version of glibc built with the
FLOATING_STACKS parameter defined. For some distributions, this
implies using the shared rather than the static version of the
pthreads library. Then use the ulimit -s or limit stacksize command to
set the maximum shell stack size to an explicit large value, in units
of KBytes, (not unlimited), and also set the KMP_STACKSIZE environment
variable to the needed thread stacksize in bytes. Note, in the bash
shell, ulimit -s can be used to set a large maximum stack size only
once. In the C shell (csh), limit stacksize , with no dash before the
argument, can be used to reset the maximum stacksize repeatedly.

This solution has been tested on glibc version 2.2.4-13 for IA-32 and
glibc 2.2.4-19 for Itanium Processor Family as found in the RedHat 7.2
Linux distribution. For glibc 2.2.4-13 on IA-32, the shared version of
the POSIX threads library must be used, (there should not be a -static
flag in the compiler .cfg file or on the command line).

In addition, if a common block is declared as THREADPRIVATE with an
OpenMP directive, the common block must have the same length in all
the source files in which it is declared. "


Intel Extension Routines/Functions:

Stack Size

In most cases, environment variables can be used in place of the
extension library routines. For example, the stack size of the
parallel threads may be set using the KMP_STACKSIZE environment
variable rather than the KMP_SET_STACKSIZE() or  KMP_SET_STACKSIZE_S()
library routine.

Note A run-time call to an Intel extension routine takes precedence
over the corresponding environment variable setting.

The routines KMP_SET_STACKSIZE() and KMP_GET_STACKSIZE() take a 32-bit
argument only. The routines KMP_SET_STACKSIZE_S() and
KMP_GET_STACKSIZE_S() take a SIZE_T argument, which can hold 64- bit
integers.

On Itanium(r)-based systems, it is recommended to always use
KMP_SET_STACKSIZE_S() and KMP_GET_STACKSIZE_S(). These _S() variants
must be used if you need to set a stack size 2**32 bytes (4
gigabytes).
Stack Size
Function
	
Description

FUNCTION KMP_GET_STACKSIZE_S()
INTEGER(KIND=KMP_SIZE_T_KIND) &
KMP_GET_STACKSIZE_S

Returns the number of bytes that will be allocated for each parallel
thread to use as its private stack. This value can be changed via the
KMP_SET_STACKSIZE_S routine, prior to the first parallel region or via
the KMP_STACKSIZE environment variable.

SUBROUTINE KMP_SET_STACKSIZE_S(size)
INTEGER (KIND=KMP_SIZE_T_KIND) size

Sets to size the number of bytes that will be allocated for each
parallel thread to use as its private stack. This value can also be
set via the KMP_STACKSIZE environment variable. In order for
KMP_SET_STACKSIZE_S to have an effect, it must be called before the
beginning of the first (dynamically executed) parallel region in the
program.

--
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Faustin Laurentiu Roman,                          Assistant Researcher
Nuclear Physics Department
"Horia Hulubei" National Institute for Physics and Nuclear Engineering
(IFIN-HH), P.O. Box MG-6, 76900 Bucharest-Magurele, Romania
Tel: 40-21-4042300/ ext. 4315, Fax: 40-21-4574432, Mobile:+40721244414
E-mail: froman_at_tandem.nipne.ro, faustinroman_at_yahoo.com
URL: http://tandem.nipne.ro/~vavrig/preeq.html
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