Memory leaks in simple MEX function

I wrote a mex function and noticed that every time I run it, more and more memory disappears from my GPU, even though I overwrite the previous results every time. In my attempts find the source of the problem, I wrote the following code (file is called MexMemoryTrack):

#include "mex.h"
#include "gpu/mxGPUArray.h"

void mexFunction(int nlhs, mxArray *plhs[],
                 int nrhs, mxArray const *prhs[])
{
    mxInitGPU();

      const mxGPUArray * inp=mxGPUCreateFromMxArray(prhs[0]);
      const mxGPUArray * ms=mxGPUCreateFromMxArray(prhs[1]);
      const double * inpPtr=(const double*) mxGPUGetDataReadOnly(inp);
      const double * masksPtr=(const double*) mxGPUGetDataReadOnly(ms);
      mxGPUArray * out=mxGPUCopyFromMxArray(prhs[2]);
      double * outPtr=(double* ) mxGPUGetData(out);
      plhs[0] = mxGPUCreateMxArrayOnGPU(out);
  mxGPUDestroyGPUArray(inp);
  mxGPUDestroyGPUArray(ms);
  mxGPUDestroyGPUArray(out);
  }

I run it using:

foo=gpuArray.zeros([3 3 10000 18]);
foo2=gpuArray.randn([7 7 10000 20]);
foo3=gpuArray.randn([5 5 18 20]);
dumdum=MexMemoryTrack(foo2,foo3,foo);

if I put this code in a loop, all my memory ends up disappearing and I get an "out of memory" error. I can't figure out why. This is a very simple code. I either overwrite data or destroy it using mxGPUDestroyGPUArray.

why would I keep losing memory? clearing dumdum after each execution doesn't help I am using Matlab 2013a and Visual Studio 2010 for compiling.

[Jill Reese]

What version of MATLAB are you using?

[Ayal]

2013a

Answer 1

[Jill Reese]

There is a known memory leak in R2013a only. If possible, I would apply the patch associated with external bug report 954239 to see if it helps in your situation.

Best,

Jill

[Ayal]

Sadly, this did not solve the problem. I deleted my own answer because it was way off. So far it seems to me like Matlab just doesn't clear the GPU memory when it's overwritten. This is a problem similar to one I've read about - when calling Matlab functions from within a MEX, memory isn't overwritten, but re-allocated.