mvapich2 and ifort: bug?

David2 — Wed, 23 Jan 2008 19:38:34 GMT

Hello Intel

I have found a strange bug in MVAPICH2 using IFORT. The behavior is very strange indeed - it seems to be related to how ifort deals with passing pointers to the MVAPICH FORTRAN 90 INTERFACE.
The MPI call returns successfully, but later calls to a dummy subroutine cause a sigsev.

Please look at the following code - sorry if the post caused formatting issues, I don't have permission to attach the file.

!=================================================================================
!=================================================================================
!=================================================================================
! TEST CODE TO FOR POSSIBLE BUG IN MVAPICH2 COMPILED ON IFORT
! WRITEN BY: DAVID STUEBE
! DATE: JAN 23, 2008
!
! COMPILE WITH: mpif90 -xP mpi_prog.f90 -o xtest
!
! KNOWN BEHAVIOR:
! PASSING A NONE CONTIGUOUS POINTER TO MPI_BCAST CAUSES FAILURE OF
! SUBROUTINES USING MULTI DIMENSIONAL EXPLICT SHAPE ARRAYS WITHOUT AN INTERFACE -
! EVEN THOUGH THE MPI_BCAST COMPLETES SUCCESUFULLY, RETURNING VALID DATA.
!
! COMMENTS:
! I REALIZE PASSING NON CONTIGUOUS POINTERS IS DANGEROUS - SHAME ON
! ME FOR MAKING THAT MISTAKE. HOWEVER, IT SHOULD EITHER WORK OR NOT.
! RETURNING SUCCESSFULLY BUT CAUSING INTERFACE ERRORS LATER IS
! EXTREMELY DIFFICULT TO DEBUG!
!
! CONDITIONS FOR OCCURANCE:
! COMPILER MUST OPTIMIZE USING 'VECTORIZATION'
! ARRAY MUST BE 'LARGE' -SYSTEM DEPENDENT ?
! MUST BE RUN ON MORE THAN ONE NODE TO CAUSE CRASH...
! ie Running inside one SMP box does not crash.
!
! RUNNING UNDER MPD, ALL PROCESSES EXIT WHEN THEY HIT DUMMY2
! RUNNING UNDER MPIEXEC0.82 FOR PBS,
! ONLY SOME PROCESSES EXIT WHEN THEY HIT DUMMY2
!
! ENVIRONMENTAL INFO:
! NODES: DELL 1850 3.0GHZ, 2GB RAM, INFINIBAND PCI-EX 4X
! SYSTEM: ROCKS 4.2
! gcc version 3.4.6 20060404 (Red Hat 3.4.6-3)
!
! IFORT/ICC:
! Intel Fortran Compiler for Intel EM64T-based applications,
! Version 9.1 Build 20061101 Package ID: l_fc_c_9.1.040
!
! MVAPICH2: mpif90 for mvapich2-1.0
! ./configure --prefix=/usr/local/share/mvapich2/1.0 --with-device=osu_ch3:mrail --with-rdma=vapi --with-pm=mpd --enable-f90 --enable-cxx --disable-romio --without-mpe
!
!=================================================================================
!=================================================================================
!=================================================================================

Module vars
USE MPI
implicit none

integer :: n,m,MYID,NPROCS
integer :: ipt

integer, allocatable, target :: data(:,:)

contains

subroutine alloc_vars
implicit none

integer Status

allocate(data(n,m),stat=status)
if (status /=0) then
write(ipt,*) "alloc ation error"
stop
end if

data = 0

end subroutine alloc_vars

SUBROUTINE INIT_MPI_ENV(ID,NP)
!===================================================================================|
! INITIALIZE MPI ENVIRONMENT |
!===================================================================================|
INTEGER, INTENT(OUT) :: ID,NP
INTEGER IERR

IERR=0

CALL MPI_INIT(IERR)
IF(IERR/=0) WRITE(*,*) "BAD MPI_INIT", ID
CALL MPI_COMM_RANK(MPI_COMM_WORLD,ID,IERR)
IF(IERR/=0) WRITE(*,*) "BAD MPI_COMM_RANK", ID
CALL MPI_COMM_SIZE(MPI_COMM_WORLD,NP,IERR)
IF(IERR/=0) WRITE(*,*) "BAD MPI_COMM_SIZE", ID

END SUBROUTINE INIT_MPI_ENV

!==============================================================================|
SUBROUTINE PSHUTDOWN
!==============================================================================|
INTEGER IERR

IERR=0
CALL MPI_FINALIZE(IERR)
if(ierr /=0) write(ipt,*) "BAD MPI_FINALIZE", MYID
close(IPT)
STOP

END SUBROUTINE PSHUTDOWN

SUBROUTINE CONTIGUOUS_WORKS
IMPLICIT NONE
INTEGER, pointer :: ptest(:,:)
INTEGER :: IERR, I,J

write(ipt,*) "START CONTIGUOUS:"
n=2000 ! Set size here
m=n+10

call alloc_vars
write(ipt,*) "ALLOCATED DATA"
ptest => data(1:N,1:N)

IF (MYID == 0) ptest=6
write(ipt,*) "Made POINTER"

call MPI_BCAST(ptest,N*N,MPI_INTEGER,0,MPI_COMM_WORLD,IERR)
IF(IERR /= 0) WRITE(IPT,*) "BAD BCAST", MYID

write(ipt,*) "BROADCAST Data; a value:",data(1,6)

DO I = 1,N
DO J = 1,N
if(data(I,J) /= 6) &
& write(ipt,*) "INCORRECT VALUE!", I,J,data(I,J)
END DO
&n bsp;
DO J = N+1,M
if(data(I,J) /= 0) &
& write(ipt,*) "INCORRECT VALUE!", I,J,data(I,J)
END DO

END DO

! CALL THREE DIFFERENT EXAMPLES OF SUBROUTINES W/OUT AN ITERFACE
! THAT USE AN EXPLICIT SHAPE ARRAY
write(ipt,*) "CALLING DUMMY1"
CALL DUMMY1

write(ipt,*) "CALLING DUMMY2"
call Dummy2(m,n)

write(ipt,*) "CALLING DUMMY3"
call Dummy3
write(ipt,*) "FINISHED!"

END SUBROUTINE CONTIGUOUS_WORKS

SUBROUTINE NON_CONTIGUOUS_FAILS
IMPLICIT NONE
INTEGER, pointer :: ptest(:,:)
INTEGER :: IERR, I,J

write(ipt,*) "START NON_CONTIGUOUS:"

m=200 ! Set size here
n=m+10

call alloc_vars
write(ipt,*) "ALLOCATED DATA"
ptest => data(1:M,1:M)

!===================================================
! IF YOU CALL DUMMY2 HERE TOO, THEN EVERYTHING PASSES ???
!===================================================
! CALL DUMMY1 ! THIS ONE HAS NO EFFECT
! CALL DUMMY2 ! THIS ONE 'FIXES' THE BUG

IF (MYID == 0) ptest=6
write(ipt,*) "Made POINTER"

call MPI_BCAST(ptest,M*M,MPI_INTEGER,0,MPI_COMM_WORLD,IERR)
IF(IERR /= 0) WRITE(IPT,*) "BAD BCAST"

write(ipt,*) "BROADCAST Data; a value:",data(1,6)

DO I = 1,M
DO J = 1,M
if(data(J,I) /= 6) &
& write(ipt,*) "INCORRECT VALUE!",I,J,DATA(I,J)
END DO

DO J = M+1,N
if(data(J,I) /= 0) &
& write(ipt,*) "INCORRECT VALUE!",I,J,DATA(I,J)
END DO
END DO

! CALL THREE DIFFERENT EXAMPLES OF SUBROUTINES W/OUT AN ITERFACE
! THAT USE AN EXPLICIT SHAPE ARRAY
write(ipt,*) "CALLING DUMMY1"
CALL DUMMY1

write(ipt,*) "CALLING DUMMY2"
call Dummy2(m,n) ! SHOULD CRASH HERE!

write(ipt,*) "CALLING DUMMY3"
call Dummy3
write(ipt,*) "FINISHED!"

END SUBROUTINE NON_CONTIGUOUS_FAILS

End Module vars

Program main
USE vars
implicit none

CALL INIT_MPI_ENV(MYID,NPROCS)

ipt=myid+10
OPEN(ipt)

write(ipt,*) "Start memory test!"

CALL NON_CONTIGUOUS_FAILS

! CALL CONTIGUOUS_WORKS

write(ipt,*) "End memory test!"

CALL PSHUTDOWN

END Program main

! TWO DUMMY SUBROUTINE WITH EXPLICIT SHAPE ARRAYS
! DUMMY1 DECLARES A VECTOR - THIS ONE NEVER CAUSES FAILURE
! DUMMY2 DECLARES AN ARRAY - THIS ONE CAUSES FAILURE

SUBROUTINE DUMMY1
USE vars
implicit none
real, dimension(m) :: my_data

write(ipt,*) "m,n",m,n

write(ipt,*) "DUMMY 1", size(my_data)

END SUBROUTINE DUMMY1

SUBROUTINE DUMMY2(i,j)
USE vars
implicit none
INTEGER, INTENT(IN) ::i,j

real, dimension(i,j) :: my_data

write(ipt,*) "start: DUMMY 2", size(my_data)

END SUBROUTINE DUMMY2

SUBROUTINE DUMMY3
USE vars
implicit none

real, dimension(m,n) :: my_data

write(ipt,*) "start: DUMMY 3", size(my_data)

END SUBROUTINE DUMMY3

Re: mvapich2 and ifort: bug?

Andrey_D_Intel — Wed, 02 Apr 2008 07:57:19 GMT

Hi,

Could youyou try the Intel MPI Library?

Best regards,

Andrey

topic mvapich2 and ifort: bug? in Intel® MPI Library

mvapich2 and ifort: bug?

Re: mvapich2 and ifort: bug?