Re: [Discuss-gnuradio] ANCI-C vs Gnuradio/C++ speeeed

[Achilleas Anastasopoulos]

I have some new data on this.

Going from ANSI-C to C++ (NO Gnuradio) using
STL vectors results in a 5-fold speed reduction!

So Gnuradio seems to be responsible for the remaining
4-fold reduction (for an overall 20-fold as I reported earlier).

I am OK with Gnuradio resulting in this 4-fold speed reduction,
but I cannot swallow the fact that STL sucks that bad :-(  !!!

I believe that this is not specific to my application, but should be 
true for any algorithm that uses vectors/matrices.
I wonder if anyone can corroborate this.

Achilleas


Robert W McGwier wrote:
> Yes.  I was comparing Phil Karn's native code to it and it runs at least 
> 20 times faster.
>
> Bob
>
>
>
> Achilleas Anastasopoulos wrote:
>
> > I have noticed a huge speed dissadvantage when comparing my
> > ANSI-C implementation of a Viterbi decoder with my Gnuradio 
> > implementation. The core code is pretty much the same, except
> > that in the Gnuradio implementation I am using STL vectors.
> >
> > It seems that Gnuradio is about 20 times SLOWER than ANSI-C!!!
> > I was wondering if this has to do with Gnuradio itself (buffering +
> > python + other fat), or with the fact that I had to translate all
> > my ANCI-C code to C++ and use STL.
> >
> > Does anyone have similar experiences?
> >
> > Achilleas