Re: [Caml-list] Memory allocation nano-benchmark.

[skaller <skaller@users.sourceforge.net>]

On Sat, 2005-02-12 at 08:07, Oliver Bandel wrote:

> > [skaller@pelican] ~>time ./zmem 250
> >  
> > real    0m3.110s
> > user    0m2.820s
> > sys     0m0.240s
> > 
> > [skaller@pelican] ~>time ./zmem 250
> >  
> > real    0m27.732s
> > user    0m2.750s
> > sys     0m0.340s
> 
> 
> Two runs, no difference?

> Are you sure zmem and zmem are the same?

Yes, its the same binary.

> 
> IMHO 
> 
> > real    0m3.110s
> > user    0m2.820s
> > sys     0m0.240s
> 
> and
> 
> > real    0m27.732s
> > user    0m2.750s
> > sys     0m0.340s
> 
> differ...

Not significantly in user time. Remember this
is not a serious measurement.

> >         table.(i).(j).(k) <- (i+1)*(j+1)*(k+1)
> > 
> > Using bigarray (c_layout):
> >  
> > real    0m27.948s
> > user    0m0.770s
> > sys     0m0.500s
> > 
> > .. 4 times faster.
> 
> ?
> 
> What is faster than what?!

The code using ordinary arrays runs in 2.8 seconds,
using bigarray 0.7 seconds. 4 x 0.7 = 2.8.

bigarray is 4 times faster to write than three level
ordinary array.


-- 
John Skaller, mailto:skaller@users.sf.net
voice: 061-2-9660-0850, 
snail: PO BOX 401 Glebe NSW 2037 Australia
Checkout the Felix programming language http://felix.sf.net