[petsc-users] Can't expand MemType 1: jcol 16104

Xiaoye S. Li xsli at lbl.gov
Mon Jul 27 23:33:27 CDT 2015


​Hong,
Thanks for trying out.
The extra printings are not properly guarded by the print level.  I will
fix that.   I will look into the hang problem soon.

Sherry
​

On Mon, Jul 27, 2015 at 7:50 PM, Hong <hzhang at mcs.anl.gov> wrote:

> Sherry,
>
> I can repeat hang using petsc/src/ksp/ksp/examples/tutorials/ex10.c:
> mpiexec -n 4 ./ex10 -f0 /homes/hzhang/tmp/Amat_binary.m -rhs 0 -pc_type lu
> -pc_factor_mat_solver_package superlu_dist -mat_superlu_dist_parsymbfact
> ...
> .. Starting with 1 OpenMP threads
> [0] .. BIG U size 1342464
> [0] .. BIG V size 131072
>   Max row size is 1311
>   Using buffer_size of 5000000
>   Threads per process 1
> ...
>
> using a debugger (with petsc option '-start_in_debugger'), I find that
> hang occurs at
> #0  0x00007f117d870998 in __GI___poll (fds=0x20da750, nfds=4,
>     timeout=<optimized out>, timeout at entry=-1)
>     at ../sysdeps/unix/sysv/linux/poll.c:83
> #1  0x00007f117de9f7de in MPIDU_Sock_wait (sock_set=0x20da550,
>     millisecond_timeout=millisecond_timeout at entry=-1,
>     eventp=eventp at entry=0x7fff654930b0)
>     at src/mpid/common/sock/poll/sock_wait.i:123
> #2  0x00007f117de898b8 in MPIDI_CH3i_Progress_wait (
>     progress_state=0x7fff65493120)
>     at src/mpid/ch3/channels/sock/src/ch3_progress.c:218
> #3  MPIDI_CH3I_Progress (blocking=blocking at entry=1,
>     state=state at entry=0x7fff65493120)
>     at src/mpid/ch3/channels/sock/src/ch3_progress.c:921
> #4  0x00007f117de1a559 in MPIR_Wait_impl (request=request at entry
> =0x262df90,
>     status=status at entry=0x7fff65493390) at src/mpi/pt2pt/wait.c:67
> #5  0x00007f117de1a818 in PMPI_Wait (request=0x262df90,
> status=0x7fff65493390)
>     at src/mpi/pt2pt/wait.c:168
> #6  0x00007f11831da557 in pzgstrf (options=0x23dfda0, m=4900, n=4900,
>     anorm=13.738475134194639, LUstruct=0x23dfe78, grid=0x23dfd78,
>     stat=0x7fff65493ea0, info=0x7fff65493edc) at pzgstrf.c:1308
>
> #7  0x00007f11831bf3bd in pzgssvx (options=0x23dfda0, A=0x23dfe30,
>     ScalePermstruct=0x23dfe50, B=0x0, ldb=1225, nrhs=0, grid=0x23dfd78,
>     LUstruct=0x23dfe78, SOLVEstruct=0x23dfe98, berr=0x0,
> stat=0x7fff65493ea0,
> ---Type <return> to continue, or q <return> to quit---
>     info=0x7fff65493edc) at pzgssvx.c:1063
>
> #8  0x00007f11825c2340 in MatLUFactorNumeric_SuperLU_DIST (F=0x23a0110,
>     A=0x21bb7e0, info=0x2355068)
>     at
> /sandbox/hzhang/petsc/src/mat/impls/aij/mpi/superlu_dist/superlu_dist.c:411
> #9  0x00007f1181c6c567 in MatLUFactorNumeric (fact=0x23a0110,
> mat=0x21bb7e0,
>     info=0x2355068) at
> /sandbox/hzhang/petsc/src/mat/interface/matrix.c:2946
> #10 0x00007f1182a56489 in PCSetUp_LU (pc=0x2353a10)
>     at /sandbox/hzhang/petsc/src/ksp/pc/impls/factor/lu/lu.c:152
> #11 0x00007f1182b16f24 in PCSetUp (pc=0x2353a10)
>     at /sandbox/hzhang/petsc/src/ksp/pc/interface/precon.c:983
> #12 0x00007f1182be61b5 in KSPSetUp (ksp=0x232c2a0)
>     at /sandbox/hzhang/petsc/src/ksp/ksp/interface/itfunc.c:332
> #13 0x0000000000405a31 in main (argc=11, args=0x7fff65499578)
>     at /sandbox/hzhang/petsc/src/ksp/ksp/examples/tutorials/ex10.c:312
>
> You may take a look at it. Sequential symbolic factorization works fine.
>
> Why superlu_dist (v4.0) in complex precision displays
>
> .. Starting with 1 OpenMP threads
> [0] .. BIG U size 1342464
> [0] .. BIG V size 131072
>   Max row size is 1311
>   Using buffer_size of 5000000
>   Threads per process 1
> ...
>
> I realize that I use superlu_dist v4.0. Would v4.1 works? I'll give it a
> try tomorrow.
>
> Hong
>
> On Mon, Jul 27, 2015 at 1:25 PM, Anthony Paul Haas <aph at email.arizona.edu>
> wrote:
>
>> Hi Hong,
>>
>> No that is not the correct matrix. Note that I forgot to mention that it
>> is a complex matrix. I tried loading the matrix I sent you this morning
>> with:
>>
>> !...Load a Matrix in Binary Format
>>       call
>> PetscViewerBinaryOpen(PETSC_COMM_WORLD,"Amat_binary.m",FILE_MODE_READ,viewer,ierr)
>>       call MatCreate(PETSC_COMM_WORLD,DLOAD,ierr)
>>       call MatSetType(DLOAD,MATAIJ,ierr)
>>       call MatLoad(DLOAD,viewer,ierr)
>>       call PetscViewerDestroy(viewer,ierr)
>>
>>       call MatView(DLOAD,PETSC_VIEWER_STDOUT_WORLD,ierr)
>>
>> The first 37 rows should look like this:
>>
>> Mat Object: 2 MPI processes
>>   type: mpiaij
>> row 0: (0, 1)
>> row 1: (1, 1)
>> row 2: (2, 1)
>> row 3: (3, 1)
>> row 4: (4, 1)
>> row 5: (5, 1)
>> row 6: (6, 1)
>> row 7: (7, 1)
>> row 8: (8, 1)
>> row 9: (9, 1)
>> row 10: (10, 1)
>> row 11: (11, 1)
>> row 12: (12, 1)
>> row 13: (13, 1)
>> row 14: (14, 1)
>> row 15: (15, 1)
>> row 16: (16, 1)
>> row 17: (17, 1)
>> row 18: (18, 1)
>> row 19: (19, 1)
>> row 20: (20, 1)
>> row 21: (21, 1)
>> row 22: (22, 1)
>> row 23: (23, 1)
>> row 24: (24, 1)
>> row 25: (25, 1)
>> row 26: (26, 1)
>> row 27: (27, 1)
>> row 28: (28, 1)
>> row 29: (29, 1)
>> row 30: (30, 1)
>> row 31: (31, 1)
>> row 32: (32, 1)
>> row 33: (33, 1)
>> row 34: (34, 1)
>> row 35: (35, 1)
>> row 36: (1, -41.2444)  (35, -41.2444)  (36, 118.049 - 0.999271 i) (37,
>> -21.447)  (38, 5.18873)  (39, -2.34856)  (40, 1.3607)  (41, -0.898206)
>> (42, 0.642715)  (43, -0.48593)  (44, 0.382471)  (45, -0.310476)  (46,
>> 0.258302)  (47, -0.219268)  (48, 0.189304)  (49, -0.165815)  (50,
>> 0.147076)  (51, -0.131907)  (52, 0.119478)  (53, -0.109189)  (54, 0.1006)
>> (55, -0.0933795)  (56, 0.0872779)  (57, -0.0821019)  (58, 0.0777011)  (59,
>> -0.0739575)  (60, 0.0707775)  (61, -0.0680868)  (62, 0.0658258)  (63,
>> -0.0639473)  (64, 0.0624137)  (65, -0.0611954)  (66, 0.0602698)  (67,
>> -0.0596202)  (68, 0.0592349)  (69, -0.0295536)  (71, -21.447)  (106,
>> 5.18873)  (141, -2.34856)  (176, 1.3607)  (211, -0.898206)  (246,
>> 0.642715)  (281, -0.48593)  (316, 0.382471)  (351, -0.310476)  (386,
>> 0.258302)  (421, -0.219268)  (456, 0.189304)  (491, -0.165815)  (526,
>> 0.147076)  (561, -0.131907)  (596, 0.119478)  (631, -0.109189)  (666,
>> 0.1006)  (701, -0.0933795)  (736, 0.0872779)  (771, -0.0821019)  (806,
>> 0.0777011)  (841, -0.0739575)  (876, 0.0707775)  (911, -0.0680868)  (946,
>> 0.0658258)  (981, -0.0639473)  (1016, 0.0624137)  (1051, -0.0611954)
>> (1086, 0.0602698)  (1121, -0.0596202)  (1156, 0.0592349)  (1191,
>> -0.0295536)  (1261, 0)  (3676, 117.211)  (3711, -58.4801)  (3746,
>> -78.3633)  (3781, 29.4911)  (3816, -15.8073)  (3851, 9.94324)  (3886,
>> -6.87205)  (3921, 5.05774)  (3956, -3.89521)  (3991, 3.10522)  (4026,
>> -2.54388)  (4061, 2.13082)  (4096, -1.8182)  (4131, 1.57606)  (4166,
>> -1.38491)  (4201, 1.23155)  (4236, -1.10685)  (4271, 1.00428)  (4306,
>> -0.919116)  (4341, 0.847829)  (4376, -0.787776)  (4411, 0.736933)  (4446,
>> -0.693735)  (4481, 0.656958)  (4516, -0.625638)  (4551, 0.599007)  (4586,
>> -0.576454)  (4621, 0.557491)  (4656, -0.541726)  (4691, 0.528849)  (4726,
>> -0.518617)  (4761, 0.51084)  (4796, -0.50538)  (4831, 0.502142)  (4866,
>> -0.250534)
>>
>>
>> Thanks,
>>
>> Anthony
>>
>>
>>
>>
>>
>> On Fri, Jul 24, 2015 at 7:56 PM, Hong <hzhang at mcs.anl.gov> wrote:
>>
>>> Anthony:
>>> I test your Amat_binary.m
>>> using petsc/src/ksp/ksp/examples/tutorials/ex10.c.
>>> Your matrix has many zero rows:
>>> ./ex10 -f0 ~/tmp/Amat_binary.m -rhs 0 -mat_view |more
>>> Mat Object: 1 MPI processes
>>>   type: seqaij
>>> row 0: (0, 1)
>>> row 1: (1, 0)
>>> row 2: (2, 1)
>>> row 3: (3, 0)
>>> row 4: (4, 1)
>>> row 5: (5, 0)
>>> row 6: (6, 1)
>>> row 7: (7, 0)
>>> row 8: (8, 1)
>>> row 9: (9, 0)
>>> ...
>>> row 36: (1, 1)  (35, 0)  (36, 1)  (37, 0)  (38, 1)  (39, 0)  (40, 1)
>>>  (41, 0)  (42, 1)  (43, 0)  (44, 1)  (45,
>>> 0)  (46, 1)  (47, 0)  (48, 1)  (49, 0)  (50, 1)  (51, 0)  (52, 1)  (53,
>>> 0)  (54, 1)  (55, 0)  (56, 1)  (57, 0)
>>>  (58, 1)  (59, 0)  (60, 1)  ...
>>>
>>> Do you send us correct matrix?
>>>
>>>>
>>>> I ran my code through valgrind and gdb as suggested by Barry. I am now
>>>> coming back to some problem I have had while running with parallel symbolic
>>>> factorization. I am attaching a test matrix (petsc binary format) that I LU
>>>> decompose and then use to solve a linear system (see code below). I can run
>>>> on 2 processors with parsymbfact or with 4 processors without parsymbfact.
>>>> However, if I run on 4 procs with parsymbfact, the code is just hanging.
>>>> Below is the simplified test case that I have used to test. The matrix A
>>>> and B are built somewhere else in my program. The matrix I am attaching is
>>>> A-sigma*B (see below).
>>>>
>>>> One thing is that I don't know for sparse matrices what is the optimum
>>>> number of processors to use for a LU decomposition? Does it depend on the
>>>> total number of nonzero? Do you have an easy way to compute it?
>>>>
>>>
>>> You have to experiment your matrix on a target machine to find out.
>>>
>>> Hong
>>>
>>>>
>>>>
>>>>
>>>>      Subroutine HowBigLUCanBe(rank)
>>>>
>>>>       IMPLICIT NONE
>>>>
>>>>       integer(i4b),intent(in) :: rank
>>>>       integer(i4b)            :: i,ct
>>>>       real(dp)                :: begin,endd
>>>>       complex(dpc)            :: sigma
>>>>
>>>>       PetscErrorCode ierr
>>>>
>>>>
>>>>       if (rank==0) call cpu_time(begin)
>>>>
>>>>       if (rank==0) then
>>>>          write(*,*)
>>>>          write(*,*)'Testing How Big LU Can Be...'
>>>>          write(*,*)'============================'
>>>>          write(*,*)
>>>>       endif
>>>>
>>>>       sigma = (1.0d0,0.0d0)
>>>>       call MatAXPY(A,-sigma,B,DIFFERENT_NONZERO_PATTERN,ierr) ! on exit
>>>> A = A-sigma*B
>>>>
>>>> !.....Write Matrix to ASCII and Binary Format
>>>>       !call PetscViewerASCIIOpen(PETSC_COMM_WORLD,"Amat.m",viewer,ierr)
>>>>       !call MatView(DXX,viewer,ierr)
>>>>       !call PetscViewerDestroy(viewer,ierr)
>>>>
>>>>       call
>>>> PetscViewerBinaryOpen(PETSC_COMM_WORLD,"Amat_binary.m",FILE_MODE_WRITE,viewer,ierr)
>>>>       call MatView(A,viewer,ierr)
>>>>       call PetscViewerDestroy(viewer,ierr)
>>>>
>>>> !.....Create Linear Solver Context
>>>>       call KSPCreate(PETSC_COMM_WORLD,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)
>>>> !aha commented and replaced by next line
>>>>       call KSPSetOperators(ksp,A,A,ierr) ! remember: here A = A-sigma*B
>>>>
>>>> !.....Set Relative and Absolute Tolerances and Uses Default for
>>>> Divergence Tol
>>>>       tol = 1.e-10
>>>>       call
>>>> KSPSetTolerances(ksp,tol,tol,PETSC_DEFAULT_REAL,PETSC_DEFAULT_INTEGER,ierr)
>>>>
>>>> !.....Set the Direct (LU) Solver
>>>>       call KSPSetType(ksp,KSPPREONLY,ierr)
>>>>       call KSPGetPC(ksp,pc,ierr)
>>>>       call PCSetType(pc,PCLU,ierr)
>>>>       call PCFactorSetMatSolverPackage(pc,MATSOLVERSUPERLU_DIST,ierr) !
>>>> MATSOLVERSUPERLU_DIST MATSOLVERMUMPS
>>>>
>>>> !.....Create Right-Hand-Side Vector
>>>>       call MatCreateVecs(A,frhs,PETSC_NULL_OBJECT,ierr)
>>>>       call MatCreateVecs(A,sol,PETSC_NULL_OBJECT,ierr)
>>>>
>>>>       allocate(xwork1(IendA-IstartA))
>>>>       allocate(loc(IendA-IstartA))
>>>>
>>>>       ct=0
>>>>       do i=IstartA,IendA-1
>>>>          ct=ct+1
>>>>          loc(ct)=i
>>>>          xwork1(ct)=(1.0d0,0.0d0)
>>>>       enddo
>>>>
>>>>       call
>>>> VecSetValues(frhs,IendA-IstartA,loc,xwork1,INSERT_VALUES,ierr)
>>>>       call VecZeroEntries(sol,ierr)
>>>>
>>>>       deallocate(xwork1,loc)
>>>>
>>>> !.....Assemble Vectors
>>>>       call VecAssemblyBegin(frhs,ierr)
>>>>       call VecAssemblyEnd(frhs,ierr)
>>>>
>>>> !.....Solve the Linear System
>>>>       call KSPSolve(ksp,frhs,sol,ierr)
>>>>
>>>>       !call VecView(sol,PETSC_VIEWER_STDOUT_WORLD,ierr)
>>>>
>>>>       if (rank==0) then
>>>>          call cpu_time(endd)
>>>>          write(*,*)
>>>>          print '("Total time for HowBigLUCanBe = ",f21.3,"
>>>> seconds.")',endd-begin
>>>>       endif
>>>>
>>>>       call SlepcFinalize(ierr)
>>>>
>>>>       STOP
>>>>
>>>>
>>>>     end Subroutine HowBigLUCanBe
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> On 07/08/2015 11:23 AM, Xiaoye S. Li wrote:
>>>>
>>>>  Indeed, the parallel symbolic factorization routine needs power of 2
>>>> processes, however, you can use however many processes you need;
>>>> internally, we redistribute matrix to nearest power of 2 processes, do
>>>> symbolic, then redistribute back to all the processes to do factorization,
>>>> triangular solve etc.  So, there is no  restriction from the users
>>>> viewpoint.
>>>>
>>>>  It's difficult to tell what the problem is.  Do you think you can
>>>> print your matrix, then, I can do some debugging by running superlu_dist
>>>> standalone?
>>>>
>>>>  Sherry
>>>>
>>>>
>>>> On Wed, Jul 8, 2015 at 10:34 AM, Anthony Paul Haas <
>>>> aph at email.arizona.edu> wrote:
>>>>
>>>>>   Hi,
>>>>>
>>>>>  I have used the switch -mat_superlu_dist_parsymbfact in my pbs
>>>>> script. However, although my program worked fine with sequential symbolic
>>>>> factorization, I get one of the following 2 behaviors when I run with
>>>>> parallel symbolic factorization (depending on the number of processors that
>>>>> I use):
>>>>>
>>>>>  1) the program just hangs (it seems stuck in some subroutine ==> see
>>>>> test.out-hangs)
>>>>>  2) I get a floating point exception ==> see
>>>>> test.out-floating-point-exception
>>>>>
>>>>>  Note that as suggested in the Superlu manual, I use a power of 2
>>>>> number of procs. Are there any tunable parameters for the parallel symbolic
>>>>> factorization? Note that when I build my sparse matrix, most elements I add
>>>>> are nonzero of course but to simplify the programming, I also add a few
>>>>> zero elements in the sparse matrix. I was thinking that maybe if the
>>>>> parallel symbolic factorization proceed by block, there could be some
>>>>> blocks where the pivot would be zero, hence creating the FPE??
>>>>>
>>>>>  Thanks,
>>>>>
>>>>>  Anthony
>>>>>
>>>>>
>>>>>
>>>>> On Wed, Jul 8, 2015 at 6:46 AM, Xiaoye S. Li <xsli at lbl.gov> wrote:
>>>>>
>>>>>>  Did you find out how to change option to use parallel symbolic
>>>>>> factorization?  Perhaps PETSc team can help.
>>>>>>
>>>>>>  Sherry
>>>>>>
>>>>>>
>>>>>> On Tue, Jul 7, 2015 at 3:58 PM, Xiaoye S. Li <xsli at lbl.gov> wrote:
>>>>>>
>>>>>>>  Is there an inquiry function that tells you all the available
>>>>>>> options?
>>>>>>>
>>>>>>>  Sherry
>>>>>>>
>>>>>>> On Tue, Jul 7, 2015 at 3:25 PM, Anthony Paul Haas <
>>>>>>> aph at email.arizona.edu> wrote:
>>>>>>>
>>>>>>>>    Hi Sherry,
>>>>>>>>
>>>>>>>>  Thanks for your message. I have used superlu_dist default
>>>>>>>> options. I did not realize that I was doing serial symbolic factorization.
>>>>>>>> That is probably the cause of my problem.
>>>>>>>>  Each node on Garnet has 60GB usable memory and I can run with
>>>>>>>> 1,2,4,8,16 or 32 core per node.
>>>>>>>>
>>>>>>>>  So I should use:
>>>>>>>>
>>>>>>>> -mat_superlu_dist_r 20
>>>>>>>> -mat_superlu_dist_c 32
>>>>>>>>
>>>>>>>>  How do you specify the parallel symbolic factorization option? is
>>>>>>>> it -mat_superlu_dist_matinput 1
>>>>>>>>
>>>>>>>>  Thanks,
>>>>>>>>
>>>>>>>>  Anthony
>>>>>>>>
>>>>>>>>
>>>>>>>> On Tue, Jul 7, 2015 at 3:08 PM, Xiaoye S. Li <xsli at lbl.gov> wrote:
>>>>>>>>
>>>>>>>>>  For superlu_dist failure, this occurs during symbolic
>>>>>>>>> factorization.  Since you are using serial symbolic factorization, it
>>>>>>>>> requires the entire graph of A to be available in the memory of one MPI
>>>>>>>>> task. How much memory do you have for each MPI task?
>>>>>>>>>
>>>>>>>>>  It won't help even if you use more processes.  You should try to
>>>>>>>>> use parallel symbolic factorization option.
>>>>>>>>>
>>>>>>>>>  Another point.  You set up process grid as:
>>>>>>>>>        Process grid nprow 32 x npcol 20
>>>>>>>>>  For better performance, you show swap the grid dimension. That
>>>>>>>>> is, it's better to use 20 x 32, never gives nprow larger than npcol.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>  Sherry
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On Tue, Jul 7, 2015 at 1:27 PM, Barry Smith <bsmith at mcs.anl.gov>
>>>>>>>>> wrote:
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>    I would suggest running a sequence of problems, 101 by 101 111
>>>>>>>>>> by 111 etc and get the memory usage in each case (when you run out of
>>>>>>>>>> memory you can get NO useful information out about memory needs). You can
>>>>>>>>>> then plot memory usage as a function of problem size to get a handle on how
>>>>>>>>>> much memory it is using.  You can also run on more and more processes
>>>>>>>>>> (which have a total of more memory) to see how large a problem you may be
>>>>>>>>>> able to reach.
>>>>>>>>>>
>>>>>>>>>>    MUMPS also has an "out of core" version (which we have never
>>>>>>>>>> used) that could in theory anyways let you get to large problems if you
>>>>>>>>>> have lots of disk space, but you are on your own figuring out how to use it.
>>>>>>>>>>
>>>>>>>>>>   Barry
>>>>>>>>>>
>>>>>>>>>> > On Jul 7, 2015, at 2:37 PM, Anthony Paul Haas <
>>>>>>>>>> aph at email.arizona.edu> wrote:
>>>>>>>>>> >
>>>>>>>>>> > Hi Jose,
>>>>>>>>>> >
>>>>>>>>>> > In my code, I use once PETSc to solve a linear system to get
>>>>>>>>>> the baseflow (without using SLEPc) and then I use SLEPc to do the stability
>>>>>>>>>> analysis of that baseflow. This is why, there are some SLEPc options that
>>>>>>>>>> are not used in test.out-superlu_dist-151x151 (when I am solving for the
>>>>>>>>>> baseflow with PETSc only). I have attached a 101x101 case for which I get
>>>>>>>>>> the eigenvalues. That case works fine. However If i increase to 151x151, I
>>>>>>>>>> get the error that you can see in test.out-superlu_dist-151x151 (similar
>>>>>>>>>> error with mumps: see test.out-mumps-151x151 line 2918 ). If you look a the
>>>>>>>>>> very end of the files test.out-superlu_dist-151x151 and
>>>>>>>>>> test.out-mumps-151x151, you will see that the last info message printed is:
>>>>>>>>>> >
>>>>>>>>>> > On Processor (after EPSSetFromOptions)  0    memory:
>>>>>>>>>> 0.65073152000E+08          =====>  (see line 807 of module_petsc.F90)
>>>>>>>>>> >
>>>>>>>>>> > This means that the memory error probably occurs in the call to
>>>>>>>>>> EPSSolve (see module_petsc.F90 line 810). I would like to evaluate how much
>>>>>>>>>> memory is required by the most memory intensive operation within EPSSolve.
>>>>>>>>>> Since I am solving a generalized EVP, I would imagine that it would be the
>>>>>>>>>> LU decomposition. But is there an accurate way of doing it?
>>>>>>>>>> >
>>>>>>>>>> > Before starting with iterative solvers, I would like to exploit
>>>>>>>>>> as much as I can direct solvers. I tried GMRES with default preconditioner
>>>>>>>>>> at some point but I had convergence problem. What solver/preconditioner
>>>>>>>>>> would you recommend for a generalized non-Hermitian (EPS_GNHEP) EVP?
>>>>>>>>>> >
>>>>>>>>>> > Thanks,
>>>>>>>>>> >
>>>>>>>>>> > Anthony
>>>>>>>>>> >
>>>>>>>>>> > On Tue, Jul 7, 2015 at 12:17 AM, Jose E. Roman <
>>>>>>>>>> jroman at dsic.upv.es> wrote:
>>>>>>>>>> >
>>>>>>>>>> > El 07/07/2015, a las 02:33, Anthony Haas escribió:
>>>>>>>>>> >
>>>>>>>>>> > > Hi,
>>>>>>>>>> > >
>>>>>>>>>> > > I am computing eigenvalues using PETSc/SLEPc and superlu_dist
>>>>>>>>>> for the LU decomposition (my problem is a generalized eigenvalue problem).
>>>>>>>>>> The code runs fine for a grid with 101x101 but when I increase to 151x151,
>>>>>>>>>> I get the following error:
>>>>>>>>>> > >
>>>>>>>>>> > > Can't expand MemType 1: jcol 16104   (and then [NID 00037]
>>>>>>>>>> 2015-07-06 19:19:17 Apid 31025976: OOM killer terminated this process.)
>>>>>>>>>> > >
>>>>>>>>>> > > It seems to be a memory problem. I monitor the memory usage
>>>>>>>>>> as far as I can and it seems that memory usage is pretty low. The most
>>>>>>>>>> memory intensive part of the program is probably the LU decomposition in
>>>>>>>>>> the context of the generalized EVP. Is there a way to evaluate how much
>>>>>>>>>> memory will be required for that step? I am currently running the debug
>>>>>>>>>> version of the code which I would assume would use more memory?
>>>>>>>>>> > >
>>>>>>>>>> > > I have attached the output of the job. Note that the program
>>>>>>>>>> uses twice PETSc: 1) to solve a linear system for which no problem occurs,
>>>>>>>>>> and, 2) to solve the Generalized EVP with SLEPc, where I get the error.
>>>>>>>>>> > >
>>>>>>>>>> > > Thanks
>>>>>>>>>> > >
>>>>>>>>>> > > Anthony
>>>>>>>>>> > > <test.out-superlu_dist-151x151>
>>>>>>>>>> >
>>>>>>>>>> > In the output you are attaching there are no SLEPc objects in
>>>>>>>>>> the report and SLEPc options are not used. It seems that SLEPc calls are
>>>>>>>>>> skipped?
>>>>>>>>>> >
>>>>>>>>>> > Do you get the same error with MUMPS? Have you tried to solve
>>>>>>>>>> linear systems with a preconditioned iterative solver?
>>>>>>>>>> >
>>>>>>>>>> > Jose
>>>>>>>>>> >
>>>>>>>>>> >
>>>>>>>>>>  >
>>>>>>>>>> <module_petsc.F90><test.out-mumps-151x151><test.out_superlu_dist-101x101><test.out-superlu_dist-151x151>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>
>>
>
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