Profile mex function in visual studio

Question

In here it is explained how to profile an .exe file in visual studio. Is there any way to profile a mex code using the same procedure?

Thanks.

Answer 1

You sure can. Just enable generation of debug info (symbols) when building the MEX file, and attach to MATLAB.exe from the Analyze->Profile menu in Visual Studio.

It's nearly the same procedure as for debugging MEX files with Visual Studio. The process is trivial if you built the MEX file with a VS project (rather than the mex command), in which case you simply enable Profiling information in the project (Linker-Advanced-Profile property), build, and then attach to MATLAB.exe from the Analyze->Profiler->Attach/detach... menu item.

If you are building with mex from MATLAB, you need to enable building a MEX file with symbolic information, but also enable optimization:

mex -g -O -largeArrayDims myMEX.cpp

I generally build MEX files from VS projects rather than with mex, so I can't say how well this latter option works, but the documentation for the -O switch suggests that you can have optimization and symbolic information generation at the same time. EDIT: It may also require editing your mexopts.bat and adding /DEBUG /PROFILE (does not disable compiler optimizations!) to LINKFLAGS. This may also allow you to omit -g from mex, but I can't say.

EDIT 2: From R2014a, MEX options are no longer managed with .bat files. Instead, look for an XML file like C:\Users\Jon\AppData\Roaming\MathWorks\MATLAB\R2014a\mex_C_win64.xml.