[mpich-discuss] Internal memory allocation error?

[Brian Harker]

Hi Rajeev-

After the master process sends the coordinates for around the
162,000th pixel, the targeted slave process fails to receive them, and
I get the error from my original post.  Thanks!

On Sun, Oct 19, 2008 at 7:11 PM, Rajeev Thakur <thakur at mcs.anl.gov> wrote:
> After how many sends and receives does it fail?
>
> Rajeev
>
>> -----Original Message-----
>> From: owner-mpich-discuss at mcs.anl.gov
>> [mailto:owner-mpich-discuss at mcs.anl.gov] On Behalf Of Brian Harker
>> Sent: Sunday, October 19, 2008 7:28 PM
>> To: mpich-discuss at mcs.anl.gov
>> Subject: Re: [mpich-discuss] Internal memory allocation error?
>>
>> Hi Rajeev-
>>
>> The code I have posted is pared down quite a bit.  I print
>> the "numsent" variable after each send and receive to make
>> sure the correct pixel has been dispatched.  I guess I should
>> mention that if I run the same program on some other data
>> that I have, which has only 68K pixels, it works flawlessly.
>>
>> On Sun, Oct 19, 2008 at 5:57 PM, Rajeev Thakur
>> <thakur at mcs.anl.gov> wrote:
>> > Brian,
>> >      This code should not even need an Irecv because the master and
>> > slave operate in lock step. And if you call Irecv followed
>> by a Wait
>> > immediately, you could as well call Recv.
>> >
>> > Since it fails with even one slave, run the 1 master 1
>> slave version
>> > and add print statements after the sends and receives to
>> see how many
>> > sends and receives are happening.
>> >
>> > Rajeev
>> >
>> >
>> >> -----Original Message-----
>> >> From: owner-mpich-discuss at mcs.anl.gov
>> >> [mailto:owner-mpich-discuss at mcs.anl.gov] On Behalf Of Brian Harker
>> >> Sent: Sunday, October 19, 2008 6:05 PM
>> >> To: mpich-discuss at mcs.anl.gov
>> >> Subject: Re: [mpich-discuss] Internal memory allocation error?
>> >>
>> >> Hi list-
>> >>
>> >> Here's my sample code for those that are wary of opening email
>> >> attachments  :)  Didn't think about that until just now.
>> >>
>> >> PROGRAM mpi_main
>> >>
>> >> USE subroutines  ! contains subroutine "invert_pixel"
>> >> IMPLICIT NONE
>> >>
>> >> INCLUDE "mpif.h"
>> >>
>> >> ! total number of pixels
>> >> INTEGER, PARAMETER :: np = nx * ny   !nx,ny specified in
>> >> module "subroutines"
>> >>
>> >> ! parameter at each pixel
>> >> DOUBLE PRECISION :: par
>> >>
>> >> ! full-size parameter array
>> >> DOUBLE PRECISION, DIMENSION(nx,ny) :: map
>> >>
>> >> ! pixel coordinates
>> >> INTEGER, DIMENSION(2) :: pxl
>> >>
>> >> ! dummy termination message
>> >> INTEGER, PARAMETER :: term = 0
>> >>
>> >> ! MPI-related
>> >> INTEGER :: proc_id
>> >> INTEGER :: proc_num
>> >> INTEGER :: master
>> >> INTEGER :: ierr
>> >> INTEGER :: sender
>> >> INTEGER :: tag
>> >> INTEGER :: numsent
>> >> INTEGER :: request
>> >> INTEGER, DIMENSION(MPI_STATUS_SIZE) :: status
>> >>
>> >> ! local indices
>> >> INTEGER :: i
>> >>
>> >>
>> !********************************************************************!
>> >> !************************** BEGIN PROGRAM
>> ***************************!
>> >>
>> !********************************************************************!
>> >> master = 0
>> >>
>> >> ! initialize MPI libraries...
>> >> CALL MPI_Init( ierr )
>> >> CALL MPI_Comm_size( MPI_COMM_WORLD, proc_num, ierr ) CALL
>> >> MPI_Comm_rank( MPI_COMM_WORLD, proc_id, ierr )
>> >>
>> >> ! --------------------------------------------- !
>> >> !             master process code               !
>> >> ! --------------------------------------------- !
>> >> IF ( proc_id == master ) THEN
>> >>
>> >>  ! dispatch first group of pixels to slave processes...
>> >>  numsent = 0
>> >>  DO i = 1, proc_num - 1
>> >>
>> >>   pxl(1) = INT(numsent/ny) + 1
>> >>   pxl(2) = MOD(numsent,ny) + 1
>> >>   CALL MPI_Send( pxl, 2, MPI_INTEGER, i, numsent+1,
>> MPI_COMM_WORLD,
>> >> ierr )
>> >>   numsent = numsent + 1
>> >>
>> >>  END DO
>> >>
>> >>  mstr: DO
>> >>
>> >>         ! receive inferred parameter back from a slave...
>> >>         CALL MPI_Recv( par, 1, MPI_DOUBLE_PRECISION,
>> MPI_ANY_SOURCE,
>> >> MPI_ANY_TAG, MPI_COMM_WORLD, status, ierr )
>> >>         sender = status(MPI_SOURCE)
>> >>         tag = status(MPI_TAG)
>> >>
>> >>         ! assemble into full-size array...
>> >>         x = INT(tag/ny) + 1
>> >>         y = MOD(tag,ny) + 1
>> >>
>> >>         map(x,y) = par
>> >>
>> >>         IF ( tag == np ) THEN
>> >>          ! all done, send termination message...
>> >>          DO j = 1, proc_num - 1
>> >>           CALL MPI_Send( term, 1, MPI_INTEGER, j, 0,
>> MPI_COMM_WORLD,
>> >> ierr )
>> >>          END DO
>> >>          EXIT mstr
>> >>         END IF
>> >>
>> >>         ! send the next available pixel to same slave...
>> >>         pxl(1) = INT((numsent+1) / ny) + 1
>> >>         pxl(2) = MOD((numsent+1), ny) + 1
>> >>
>> >>         CALL MPI_Send( pxl, 2, MPI_INTEGER, sender,
>> >> numsent+1, MPI_COMM_WORLD, ierr )
>> >>         numsent = numsent + 1
>> >>
>> >>        END DO mstr
>> >> ! --------------------------------------------- !
>> >> !              slave process code               !
>> >> ! --------------------------------------------- !
>> >> ELSE
>> >>
>> >>  slv: DO
>> >>
>> >>        ! receive pixel coordinates from master...
>> >>        CALL MPI_Irecv( pxl, 2, MPI_INTEGER, master, MPI_ANY_TAG,
>> >> MPI_COMM_WORLD, request, ierr )
>> >>        CALL MPI_Wait( request, status, ierr )
>> >>        tag = status(MPI_TAG)
>> >>        IF ( tag == 0 ) THEN
>> >>         ! all done, exit program...
>> >>         EXIT slv
>> >>        END IF
>> >>
>> >>        ! call genetic algorithm for inversion...
>> >>        CALL invert_pixel( pxl, par )
>> >>
>> >>        ! send parameter result back to master...
>> >>        CALL MPI_Send( par, 1, MPI_DOUBLE_PRECISION, master, tag,
>> >> MPI_COMM_WORLD, ierr )
>> >>       END DO slv
>> >>
>> >> END IF
>> >>
>> >> ! shut down MPI...
>> >> CALL MPI_Finalize( ierr )
>> >> WRITE(*,*) ""
>> >> IF ( ierr == 0 ) WRITE(*,*) "Goodbye from process",proc_id
>> >>
>> >>
>> !********************************************************************!
>> >> !**************************** END PROGRAM
>> ***************************!
>> >>
>> !********************************************************************!
>> >>
>> >> STOP
>> >> END PROGRAM mpi_main
>> >>
>> >>
>> >>
>> >>
>> >> --
>> >> Cheers,
>> >> Brian
>> >> brian.harker at gmail.com
>> >>
>> >>
>> >> "In science, there is only physics; all the rest is
>> stamp-collecting."
>> >>
>> >> -Ernest Rutherford
>> >>
>> >>
>> >
>> >
>>
>>
>>
>> --
>> Cheers,
>> Brian
>> brian.harker at gmail.com
>>
>>
>> "In science, there is only physics; all the rest is stamp-collecting."
>>
>> -Ernest Rutherford
>>
>>
>
>



-- 
Cheers,
Brian
brian.harker at gmail.com


"In science, there is only physics; all the rest is stamp-collecting."

-Ernest Rutherford