[petsc-dev] Valgrind defect: memory leak with PetscCommDuplicate?

Brendan Kochunas bkochuna at umich.edu
Fri Feb 6 13:17:07 CST 2015


Hi Barry/Boyce,

I did a bit more digging and was able to reproduce this defect using a  
slightly modified version of ex2f.F located at: 
http://www.mcs.anl.gov/petsc/petsc-3.3/src/ksp/ksp/examples/tutorials/ex2f.F

I have pasted this modified version below. Essentially the modification 
replaces PETSC_COMM_WORLD with a duplicate comm of MPI_COMM_SELF in each 
of the Mat/Vec/KSPCreate calls. (tested with 1 mpi proc)

I'll note that the defect was NOT reported if a duplicate of 
PETSC_COMM_WORLD was used or if MPI_COMM_WORLD was used or a duplicate 
of it was used.

It should be worthwhile to test this modified example against mpich to 
confirm that the OpenMPI is the culprit in this case.

I have had similar experiences between MPICH and OpenMPI, so I would not 
be surprised in the least if OpenMPI is the source of the leak.

Thanks,
-Brendan

!
!  Description: Solves a linear system in parallel with KSP (Fortran code).
!               Also shows how to set a user-defined monitoring routine.
!
!  Program usage: mpiexec -n <procs> ex2f [-help] [all PETSc options]
!
!/*T
!  Concepts: KSP^basic parallel example
!  Concepts: KSP^setting a user-defined monitoring routine
!  Processors: n
!T*/
!
! -----------------------------------------------------------------------

       program main
       implicit none

! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!                    Include files
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!
!  This program uses CPP for preprocessing, as indicated by the use of
!  PETSc include files in the directory petsc/include/finclude. This
!  convention enables use of the CPP preprocessor, which allows the use
!  of the #include statements that define PETSc objects and variables.
!
!  Use of the conventional Fortran include statements is also supported
!  In this case, the PETsc include files are located in the directory
!  petsc/include/foldinclude.
!
!  Since one must be very careful to include each file no more than once
!  in a Fortran routine, application programmers must exlicitly list
!  each file needed for the various PETSc components within their
!  program (unlike the C/C++ interface).
!
!  See the Fortran section of the PETSc users manual for details.
!
!  The following include statements are required for KSP Fortran programs:
!     petscsys.h       - base PETSc routines
!     petscvec.h    - vectors
!     petscmat.h    - matrices
!     petscpc.h     - preconditioners
!     petscksp.h    - Krylov subspace methods
!  Additional include statements may be needed if using additional
!  PETSc routines in a Fortran program, e.g.,
!     petscviewer.h - viewers
!     petscis.h     - index sets
!
#include <finclude/petscsys.h>
#include <finclude/petscvec.h>
#include <finclude/petscmat.h>
#include <finclude/petscpc.h>
#include <finclude/petscksp.h>
!
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!                   Variable declarations
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!
!  Variables:
!     ksp     - linear solver context
!     ksp      - Krylov subspace method context
!     pc       - preconditioner context
!     x, b, u  - approx solution, right-hand-side, exact solution vectors
!     A        - matrix that defines linear system
!     its      - iterations for convergence
!     norm     - norm of error in solution
!     rctx     - random number generator context
!
!  Note that vectors are declared as PETSc "Vec" objects.  These vectors
!  are mathematical objects that contain more than just an array of
!  double precision numbers. I.e., vectors in PETSc are not just
!        double precision x(*).
!  However, local vector data can be easily accessed via VecGetArray().
!  See the Fortran section of the PETSc users manual for details.
!
       integer testComm
       double precision  norm
       PetscInt  i,j,II,JJ,m,n,its
       PetscInt  Istart,Iend,ione
       PetscErrorCode ierr
       PetscMPIInt     rank,size
       PetscBool   flg
       PetscScalar v,one,neg_one
       Vec         x,b,u
       Mat         A
       KSP         ksp
       PetscRandom rctx

!  These variables are not currently used.
!      PC          pc
!      PCType      ptype
!      double precision tol


!  Note: Any user-defined Fortran routines (such as MyKSPMonitor)
!  MUST be declared as external.

       external MyKSPMonitor,MyKSPConverged

! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!                 Beginning of program
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

       call PetscInitialize(PETSC_NULL_CHARACTER,ierr)
       m = 3
       n = 3
       one  = 1.0
       neg_one = -1.0
       ione    = 1
       call PetscOptionsGetInt(PETSC_NULL_CHARACTER,'-m',m,flg,ierr)
       call PetscOptionsGetInt(PETSC_NULL_CHARACTER,'-n',n,flg,ierr)
       call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr)
       call MPI_Comm_size(PETSC_COMM_WORLD,size,ierr)
!      call MPI_Comm_dup(MPI_COMM_SELF,testComm,ierr)
       testComm=MPI_COMM_SELF

! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!      Compute the matrix and right-hand-side vector that define
!      the linear system, Ax = b.
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

!  Create parallel matrix, specifying only its global dimensions.
!  When using MatCreate(), the matrix format can be specified at
!  runtime. Also, the parallel partitioning of the matrix is
!  determined by PETSc at runtime.

       call MatCreate(testComm,A,ierr)
       call MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n,ierr)
       call MatSetFromOptions(A,ierr)
       call MatSetUp(A,ierr)

!  Currently, all PETSc parallel matrix formats are partitioned by
!  contiguous chunks of rows across the processors.  Determine which
!  rows of the matrix are locally owned.

       call MatGetOwnershipRange(A,Istart,Iend,ierr)

!  Set matrix elements for the 2-D, five-point stencil in parallel.
!   - Each processor needs to insert only elements that it owns
!     locally (but any non-local elements will be sent to the
!     appropriate processor during matrix assembly).
!   - Always specify global row and columns of matrix entries.
!   - Note that MatSetValues() uses 0-based row and column numbers
!     in Fortran as well as in C.

!     Note: this uses the less common natural ordering that orders first
!     all the unknowns for x = h then for x = 2h etc; Hence you see JH = 
II +- n
!     instead of JJ = II +- m as you might expect. The more standard 
ordering
!     would first do all variables for y = h, then y = 2h etc.

       do 10, II=Istart,Iend-1
         v = -1.0
         i = II/n
         j = II - i*n
         if (i.gt.0) then
           JJ = II - n
           call MatSetValues(A,ione,II,ione,JJ,v,INSERT_VALUES,ierr)
         endif
         if (i.lt.m-1) then
           JJ = II + n
           call MatSetValues(A,ione,II,ione,JJ,v,INSERT_VALUES,ierr)
         endif
         if (j.gt.0) then
           JJ = II - 1
           call MatSetValues(A,ione,II,ione,JJ,v,INSERT_VALUES,ierr)
         endif
         if (j.lt.n-1) then
           JJ = II + 1
           call MatSetValues(A,ione,II,ione,JJ,v,INSERT_VALUES,ierr)
         endif
         v = 4.0
         call  MatSetValues(A,ione,II,ione,II,v,INSERT_VALUES,ierr)
  10   continue

!  Assemble matrix, using the 2-step process:
!       MatAssemblyBegin(), MatAssemblyEnd()
!  Computations can be done while messages are in transition,
!  by placing code between these two statements.

       call MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY,ierr)
       call MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY,ierr)

!  Create parallel vectors.
!   - Here, the parallel partitioning of the vector is determined by
!     PETSc at runtime.  We could also specify the local dimensions
!     if desired -- or use the more general routine VecCreate().
!   - When solving a linear system, the vectors and matrices MUST
!     be partitioned accordingly.  PETSc automatically generates
!     appropriately partitioned matrices and vectors when MatCreate()
!     and VecCreate() are used with the same communicator.
!   - Note: We form 1 vector from scratch and then duplicate as needed.

       call VecCreateMPI(testComm,PETSC_DECIDE,m*n,u,ierr)
       call VecSetFromOptions(u,ierr)
       call VecDuplicate(u,b,ierr)
       call VecDuplicate(b,x,ierr)

!  Set exact solution; then compute right-hand-side vector.
!  By default we use an exact solution of a vector with all
!  elements of 1.0;  Alternatively, using the runtime option
!  -random_sol forms a solution vector with random components.

       call PetscOptionsHasName(PETSC_NULL_CHARACTER,                    &
      &             "-random_exact_sol",flg,ierr)
       if (flg) then
          call PetscRandomCreate(testComm,rctx,ierr)
          call PetscRandomSetFromOptions(rctx,ierr)
          call VecSetRandom(u,rctx,ierr)
          call PetscRandomDestroy(rctx,ierr)
       else
          call VecSet(u,one,ierr)
       endif
       call MatMult(A,u,b,ierr)

!  View the exact solution vector if desired

       call PetscOptionsHasName(PETSC_NULL_CHARACTER,                    &
      &             "-view_exact_sol",flg,ierr)
       if (flg) then
          call VecView(u,PETSC_VIEWER_STDOUT_WORLD,ierr)
       endif

! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!         Create the linear solver and set various options
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

!  Create linear solver context

       call KSPCreate(testComm,ksp,ierr)

!  Set operators. Here the matrix that defines the linear system
!  also serves as the preconditioning matrix.

       call KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN,ierr)

!  Set linear solver defaults for this problem (optional).
!   - By extracting the KSP and PC contexts from the KSP context,
!     we can then directly directly call any KSP and PC routines
!     to set various options.
!   - The following four statements are optional; all of these
!     parameters could alternatively be specified at runtime via
!     KSPSetFromOptions(). All of these defaults can be
!     overridden at runtime, as indicated below.

!     We comment out this section of code since the Jacobi
!     preconditioner is not a good general default.

!      call KSPGetPC(ksp,pc,ierr)
!      ptype = PCJACOBI
!      call PCSetType(pc,ptype,ierr)
!      tol = 1.e-7
!      call KSPSetTolerances(ksp,tol,PETSC_DEFAULT_DOUBLE_PRECISION,
!     & PETSC_DEFAULT_DOUBLE_PRECISION,PETSC_DEFAULT_INTEGER,ierr)

!  Set user-defined monitoring routine if desired

       call PetscOptionsHasName(PETSC_NULL_CHARACTER,'-my_ksp_monitor',  &
      &                    flg,ierr)
       if (flg) then
         call KSPMonitorSet(ksp,MyKSPMonitor,PETSC_NULL_OBJECT,          &
      &                     PETSC_NULL_FUNCTION,ierr)
       endif


!  Set runtime options, e.g.,
!      -ksp_type <type> -pc_type <type> -ksp_monitor -ksp_rtol <rtol>
!  These options will override those specified above as long as
!  KSPSetFromOptions() is called _after_ any other customization
!  routines.

       call KSPSetFromOptions(ksp,ierr)

!  Set convergence test routine if desired

       call PetscOptionsHasName(PETSC_NULL_CHARACTER,                    &
      &     '-my_ksp_convergence',flg,ierr)
       if (flg) then
         call KSPSetConvergenceTest(ksp,MyKSPConverged,                  &
      &          PETSC_NULL_OBJECT,PETSC_NULL_FUNCTION,ierr)
       endif
!
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!                      Solve the linear system
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

       call KSPSolve(ksp,b,x,ierr)

! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
!                     Check solution and clean up
! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

!  Check the error
       call VecAXPY(x,neg_one,u,ierr)
       call VecNorm(x,NORM_2,norm,ierr)
       call KSPGetIterationNumber(ksp,its,ierr)
       if (rank .eq. 0) then
         if (norm .gt. 1.e-12) then
            write(6,100) norm,its
         else
            write(6,110) its
         endif
       endif
   100 format('Norm of error ',e11.4,' iterations ',i5)
   110 format('Norm of error < 1.e-12,iterations ',i5)

!  Free work space.  All PETSc objects should be destroyed when they
!  are no longer needed.

       call KSPDestroy(ksp,ierr)
       call VecDestroy(u,ierr)
       call VecDestroy(x,ierr)
       call VecDestroy(b,ierr)
       call MatDestroy(A,ierr)

!  Always call PetscFinalize() before exiting a program.  This routine
!    - finalizes the PETSc libraries as well as MPI
!    - provides summary and diagnostic information if certain runtime
!      options are chosen (e.g., -log_summary).  See PetscFinalize()
!      manpage for more information.

       call PetscFinalize(ierr)
       end

! --------------------------------------------------------------
!
!  MyKSPMonitor - This is a user-defined routine for monitoring
!  the KSP iterative solvers.
!
!  Input Parameters:
!    ksp   - iterative context
!    n     - iteration number
!    rnorm - 2-norm (preconditioned) residual value (may be estimated)
!    dummy - optional user-defined monitor context (unused here)
!
       subroutine MyKSPMonitor(ksp,n,rnorm,dummy,ierr)

       implicit none

#include <finclude/petscsys.h>
#include <finclude/petscvec.h>
#include <finclude/petscksp.h>

       KSP              ksp
       Vec              x
       PetscErrorCode ierr
       PetscInt n,dummy
       PetscMPIInt rank
       double precision rnorm

!  Build the solution vector

       call KSPBuildSolution(ksp,PETSC_NULL_OBJECT,x,ierr)

!  Write the solution vector and residual norm to stdout
!   - Note that the parallel viewer PETSC_VIEWER_STDOUT_WORLD
!     handles data from multiple processors so that the
!     output is not jumbled.

       call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr)
       if (rank .eq. 0) write(6,100) n
       call VecView(x,PETSC_VIEWER_STDOUT_WORLD,ierr)
       if (rank .eq. 0) write(6,200) n,rnorm

  100  format('iteration ',i5,' solution vector:')
  200  format('iteration ',i5,' residual norm ',e11.4)
       ierr = 0
       end

! --------------------------------------------------------------
!
!  MyKSPConverged - This is a user-defined routine for testing
!  convergence of the KSP iterative solvers.
!
!  Input Parameters:
!    ksp   - iterative context
!    n     - iteration number
!    rnorm - 2-norm (preconditioned) residual value (may be estimated)
!    dummy - optional user-defined monitor context (unused here)
!
       subroutine MyKSPConverged(ksp,n,rnorm,flag,dummy,ierr)

       implicit none

#include <finclude/petscsys.h>
#include <finclude/petscvec.h>
#include <finclude/petscksp.h>

       KSP              ksp
       PetscErrorCode ierr
       PetscInt n,dummy
       KSPConvergedReason flag
       double precision rnorm

       if (rnorm .le. .05) then
         flag = 1
       else
         flag = 0
       endif
       ierr = 0

       end



On 2/6/2015 2:13 PM, Boyce Griffith wrote:
>> On Feb 6, 2015, at 2:04 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
>>
>>
>>   If you don't see any memory leaks directly from PETSc routines then it is a problem in OpenMPI.
> OpenMPI intentionally does stuff that is not Valgrind clean:
>
> http://www.open-mpi.org/faq/?category=debugging#valgrind_clean
>
> I've personally had mixed success with the OpenMPI-provided suppression file in the past, but I haven't tried it in a while.
>
> -- Boyce
>
>>   We've found that MPICH seems to have less memory leaks than OpenMPI.
>>
>>    Barry
>>
>>> On Feb 6, 2015, at 8:52 AM, Brendan Kochunas <bkochuna at umich.edu> wrote:
>>>
>>> Hi we are trying to clear valgrind defects from our code and presently we are valgrind is reporting memory leaks like the following:
>>>
>>> ==2884==    at 0x4A07EB7: malloc (vg_replace_malloc.c:296)
>>> ==2884==    by 0x8519874: set_value.isra.0.part.1 (in /gcc-4.6.1/toolset/openmpi-1.4.3/lib/libmpi.so.0.0.2)
>>> ==2884==    by 0x8547E4D: PMPI_Attr_put (in /gcc-4.6.1/toolset/openmpi-1.4.3/lib/libmpi.so.0.0.2)
>>> ==2884==    by 0x113A153: PetscCommDuplicate
>>> ==2884==    by 0x113BFA3: PetscHeaderCreate_Private
>>> ==2884==    by 0x129ADC6: MatCreate
>>> ==2884==    by 0x123C355: MatMPIAIJSetPreallocation_MPIAIJ
>>> ==2884==    by 0x124DAB4: MatMPIAIJSetPreallocation
>>> ==2884==    by 0x12549B0: MatSetUp_MPIAIJ
>>> ==2884==    by 0x1191186: MatSetUp
>>> ==2884==    by 0x10D9333: matsetup_
>>>
>>> and...
>>>
>>> ==2884==    at 0x4A07EB7: malloc (vg_replace_malloc.c:296)
>>> ==2884==    by 0x8519874: set_value.isra.0.part.1 (in /gcc-4.6.1/toolset/openmpi-1.4.3/lib/libmpi.so.0.0.2)
>>> ==2884==    by 0x8547E4D: PMPI_Attr_put (in /gcc-4.6.1/toolset/openmpi-1.4.3/lib/libmpi.so.0.0.2)
>>> ==2884==    by 0x113A22D: PetscCommDuplicate
>>> ==2884==    by 0x113BFA3: PetscHeaderCreate_Private
>>> ==2884==    by 0x10ED42B: KSPCreate
>>> ==2884==    by 0x10DA55C: kspcreate_
>>>
>>> Is the development team aware of any memory leaks that may be coming from PetscCommDuplicate as it may be used in the call stack shown above?
>>>
>>> The version of PETSc we are linking with is 3.3 patch 4. And this is built on OpenMPI v. 1.4.3.
>>>
>>> We are trying to determine if the leak is due to
>>> 1. Our codes usage of PETSc
>>> 2. The actual PETSc library
>>> 3. PETSc's usage of MPI
>>> 3. The OpenMPI library that PETSc was built against
>>>
>>> Any assistance in being able to point to the culprit or suggestions for particular tests (e.g. a PETSc example) worth trying to identify the root issue would be appreciated.
>>>
>>> Thanks in advance!
>>> -Brendan
>>>




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