Re: For loop benchmarks between Octave versions

[Julien Bect]

Le 17/06/2014 02:39, Rik a écrit :
> I find that this changeset:
>
> 12920:5d18231eee00 Extend profiling support to operators.
>
> produces a 50% slow down when using the for loop benchmark. Unless we 
> can figure out a lower footprint way to do profiling we might be stuck 
> with this part of the slowdown. There is still another 50% which seems 
> to be due to other accumulated cruft, i.e., I didn't find a smoking 
> gun changeset.

On the gui-release branch, I notice a clear 10% increase on the for loop 
benchmark between

    1ec884e5ff00   waitbar.m: Force pixel units for waitbar figure (bug 
#41645)
http://hg.savannah.gnu.org/hgweb/octave/rev/1ec884e5ff00

and

    554be77a60fb   Add FT2_CFLAGS to CPPFLAGS required for new Qt graphics.
http://hg.savannah.gnu.org/hgweb/octave/rev/554be77a60fb.

All changesets inbetween are related to QtHandles, especially this one :

    18498:2e7cad6f180c   Initial integration of QtHandles.
http://hg.savannah.gnu.org/hgweb/octave/rev/2e7cad6f180c

Does anyone have a clue on why the integration of QtHandles might have 
affected the computation time of a simple loop ?

(Note : all tests done with ./run-octave --no-gui on Ubuntu 13.04 with 
gcc 4.7.3 i686-linux-gnu, --enable-jit)