Re: Performance: Octave vs. Matlab

[wkim+]

> From: "John Eaton" <address@hidden>
> To: address@hidden
> 
> address@hidden wrote:
> 
> : And, for the same program (translated keywords only), octave 1.1.0 for
> : OS/2 gave 32 seconds which is about 3 times slower than Matlab for Win.
> : and cannot be said as "slight" overheads.  How do you think?
> 
> Running this on a SPARCstation 2 with 1.1.1 took 160 CPU seconds.
> With the current development version, it took 135.  Maybe this could
> be even better if someone were to spend some time working on it.  (I
> probably won't spend much time on it, since there are many things that
> I think are more important to work on right now.)
 
Could you tell me what optimization level was used when compiling
Octave 1.1.0 for OS/2 with emx/gcc 0.9a?

I remember that -O switches (of gcc 2.6.3) gave weird results in 
exection speed.  A funny result was that -O2 (which is the default)
generated slower code than no optimization for a simple loop test 
(like the one I posted before here.) if loop variables are 'double' 
instead of 'int'.  I posted it to emx-list and people reported the
same problem and so I sent a bug report to bug-gcc a month ago. 
(A person posted that he identified the source of the bug.)
I suspect that Octave's slow performance might come from gcc's 
fault (in dealing with floating-point math).

Thanks.

//--------------------------------------------------------------------
// Wonkoo Kim
// address@hidden