On Aug 10, 2010, at 5:58 PM, thdox wrote:

> Your results are :
> 
> > using an "acprep opt" build on a 2.26GHz Core i7 (all output going to 
> > /dev/null):
> >
> >    reg, no flags       5.00s
> >    reg, -V            13.39s
> >    reg, -X            12.91s
> 
> My results are, on a AMD Athlon(tm) Dual Core Processor 4850e, 2500MHz, 64 
> bits
>  
> $ time ledger reg        > /dev/null
> real    0m12.727s
> $ time ledger reg -X € > /dev/null
> real    2m8.355s
> 
> The ratio are 12.7/5=2.54 and 128.355/12.91=9.94
> 
> When my ledger executable is running I can see that only one core is used. I 
> suspect you used a compilation option that enables ledger executable to use 
> several cores when running. Am I right ? What is this option ? 

This is troubling.  Ledger only ever uses one core, however it uses main memory 
pretty
heavily.  So the fact that my i7 has direct access to main memory could account 
for a bit of the difference.  But an order of magnitude?  Also, on OS X I'm 
using the -fast option to gcc, which is often 2-3x faster than -O3.  What 
version of gcc do you have?

John

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