[hashcash] Re: status of hashcash version 1?

  • From: Jonathan Morton <chromi@xxxxxxxxxxxxxxxxxxxxx>
  • To: hashcash@xxxxxxxxxxxxx
  • Date: Tue, 3 Aug 2004 15:44:29 +0100

Compile flags are just: -O3 -funroll-loops  -DREGEXP_POSIX
I'll play with the flags later to see if I can find any thing that
makes it faster.  Any suggestions?

Yes - compile specifically for your CPU model. On x86 this is done using (for example) -march=athlon-xp, on PPC it's done using (for example) -mcpu=7450. Look up the info page for GCC to find the options for your platform.


Without knowledge of the specific model to compile for, GCC will use a generic model which will run on any CPU from the architecture, but probably not as fast as it might do. I'm afraid this code is rather sensitive to that, particularly on architectures with long pipelines and/or large numbers of execution units but poor out-of-order execution.

--------------------------------------------------------------
from:     Jonathan "Chromatix" Morton
mail:     chromi@xxxxxxxxxxxxxxxxxxxxx
website:  http://www.chromatix.uklinux.net/
tagline:  The key to knowledge is not to rely on people to teach you it.


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