[petsc-dev] valgrind appears to show memory leak related to PetscViewerBinaryOpen

[Brad Aagaard]

Barry-

Thanks for the correction. I was under the impression that I needed to 
create and then open.

Yes, I am aware of all the noise that OpenMPI creates with valgrind. 
Matt's memory allocation stuff in Sieve also creates lots of noise with 
valgrind but at least they show 0 bytes leaked.

Thanks,
Brad

On 06/01/2011 09:20 AM, Barry Smith wrote:
>
>     Brad,
>
>      The problems valgrind reports are all due to errors in opempi. If you use --download-mpich that installs a "clean" version of MPICH that has no memory errors.
>
>     The [0] means process 0.
>
>     The "memory leak reported by -malloc_dump is due to bad example code
>
> err = PetscViewerBinaryCreate(PETSC_COMM_WORLD,&viewer);CHKERRQ(err);
>
>    err = PetscViewerBinaryOpen(PETSC_COMM_WORLD, "myviewer.dat", FILE_MODE_WRITE,&viewer); CHKERRQ(err);
>
>      There is no reason for the line PetscViewerBinaryCreate(). It creates an (unfilled) binary viewer but then PetscViewerBinaryOpen() lies on top of it a filled one, thus leaking the previous memory.
>
>     There is no reason for the existence of PetscViewerBinaryCreate(), I am removing it from PETSc-dev.
>
>
>
>      Barry
>
>
>
>    On Jun 1, 2011, at 11:05 AM, Brad Aagaard wrote:
>
>> Hi all:
>>
>> Valgrind is suggesting that I may have a memory leak associated with PetscViewer objects in PyLith. I created a simple example (attached) that reproduces the valgrind message.
>>
>> Is there really a memory leak associated with PetscMallocAlign() or is valgrind just confused?
>>
>> I also ran the example with the -malloc -malloc_debug -malloc_dump flags. What do the values in square brackets mean? Does [0] indicate memory was freed or not freed? The FAQ on use of -malloc doesn't appear to discuss what the output means.
>>
>> Logs from running the example in valgrind and with the malloc flags are also attached.
>>
>> Thanks,
>> Brad
>> <log_malloc.txt><log_valgrind.txt><test_viewer.cc>
>
>