Re: factor is too fast

[Toralf Förster]

At Monday 27 April 2009 08:35:11 Mike Frysinger wrote :
> On Tuesday 21 April 2009 08:19:23 Philip Rowlands wrote:
> > On Tue, 21 Apr 2009, Toralf F?rster wrote:
> > > For a long time I used the command "factor" to test my system WRT the
> > > cpu ondemand governor of the linux kernel, eg for issues like this :
> > > http://bugzilla.kernel.org/show_bug.cgi?id=12385
> > >
> > > However switching from coreutils-6.10 to 7.1 (stable Gentoo Linux) now
> > > the factor command is too fast: it takes only 0.003 sec instead of 5.5
> > > sec for the same prime number.
> >
> > That's probably due to this entry from NEWS:
> >
> > * Noteworthy changes in release 7.0 (2008-10-05) [beta]
> >
> >    If the GNU MP library is available at configure time, factor and
> >    expr support arbitrarily large numbers.  Pollard's rho algorithm is
> >    used to factor large numbers.
>
> if GMP is too fast, then you could try building coreutils with USE=gmp.  if
> coreutils itself got a new algo, then i guess save the old binary ...
> -mike

Thx,

I like this speed improvement in general - and this was really impressive - 
and b/c I was pointed to the command timeout
BTW this has the advantage that I do not have to wait 3x longer (600 MHz 
versus 1700 MZh) to realize that the ondemand governor doesn't work
:-)

-- 
MfG/Sincerely

Toralf Förster
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