Re: Performance issues on Windows, suggests a MSVC build

[Michael Goffioul]

On Wed, Jun 22, 2011 at 11:47 AM, Ole Jacob Hagen
<address@hidden> wrote:
> * Linux: File loading + plotting: 3 minutes
>
> * Windows XP(MinGw): File loading + plotting: 30-40 minutes.
>
> File loading operation eg data = load('myoversizedlogfile.txt') is using
> 80-90% of total time.
>
> Can a pure MSVC build increase performance of data files with that size, or
> is Octave purely meant for people who has never created a proper log file?
> <jokingly> ;-)

I may be wrong, but I don't think using MSVC will make a big difference.
Basically, MinGW is using the same runtime libs as VC++ [1].
Do you use the same hardware in Linux and Windows cases?

> I've read some discussion whether to support a MSVC build, or at least keep
> it compilable.
> But the VC runtime library license  was conflicting with GPL....as I
> understood it.
>
> Why does other GPL software on Windows ships VC run time library with their
> GPL'ed software?

At the time the issue was raised, the GPL FAQ entry you mention didn't exist
and the situation was unclear. One CLN/GiNaC developer claimed I was violating
GPL by distributing MSVC-compiled binaries, as the VC++ runtime libs didn't
qualify as system libs. The situation has been now clarified. However it only
concerns the linking issue. Shipping VC++ runtime libs is another story and
the MS license most probably prevents you from doing it (at least when not using
a commercial version of VC++).

In the end, that episode, plus the constant "get yourself a better
compiler" answer
I got when reporting compilation issues with MSVC, just removed all
the fun I had
in providing MSVC binaries for octave. So I dropped the whole stuff
and continued
to support MSVC just for myself.

> Since Octave is supported on all platforms, it is therefore not "trapped" by
> any Operating System, is it?

Octave is a GNU project, and as such, is dedicated to be compiled with GNU
compiler and run on a GNU operating system. It may run on other platforms and
be compiled with other compilers, but this is not a target.

Michael.

[1] This is not entirely true, as from MSVC9 (aka Visual Studio 2008), the VC++
runtime libs are not linked anymore to MSVCRT.DLL, which is used by MinGW.
Maybe one day, MS will stop shipping and linking to MSVCRT.DLL, such that
it won't qualify as a system lib anymore. That can be funny...