/RTCs compiler option

[bpluymer]

Hello,

I have a problem with my C++ code in that my code is faster in Debug
mode than in Release mode. The reason for this are calls upon
routines from a C compiled lib that I am using (Umfpack).

When I compile my code with the /RTCs option (like in Debug mode) the
Umfpack routines I call upon are fast.

When I do not use /RTCs but the "default" option of Visual Studio
.NET,
the Umfpack routines I call upon are very slow (however I link with
the same Umfpack_43.lib file).

Does anybody know what might be the problem?

Thanks,
Bert

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[Fredrik Wahlgren]

Hello,

I have a problem with my C++ code in that my code is faster in Debug
mode than in Release mode. The reason for this are calls upon
routines from a C compiled lib that I am using (Umfpack).

When I compile my code with the /RTCs option (like in Debug mode) the
Umfpack routines I call upon are fast.

When I do not use /RTCs but the "default" option of Visual Studio
NET,
the Umfpack routines I call upon are very slow (however I link with
the same Umfpack_43.lib file).

Does anybody know what might be the problem?

Thanks,
Bert

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Posted at:
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How weird. Here's a wild guess. Let's assume there are two versions of
umpack, debug and release. LEts also assume that your release version calls
the dbug version of umfpack. Now, I don't know well hoew debuggers work
interbnally but I guess there's code within that sets up certain things. My
guess is that each call to umfpack would force it do the setup and that is
lost afterwards. The debug version of your code retains these settings. Does
this make sense?

/ Fredrik

 

[bpluymer]

Hi Fredrik,

I understand what you mean, but linking to the debug version of
Umfpack does not change the behaviour. Well it does in the sense that
everything becomes slower, but calls made with the /RTCs are still a
lot faster than calls made without it.

Regards,
Bert

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Posted at:
www.GroupSrv.com
*-----------------------*