Will GPG use Dual Processors under Windows ?

David Shaw dshaw@jabberwocky.com
Tue Nov 19 02:06:01 2002

On Mon, Nov 18, 2002 at 03:34:02PM -0500, Jason_Mantor@hesc.com wrote:
>       We're designing the next iteration of our encrypted file transmission
> systems and we're anticipating the need to encrypt and decrypt files that
> could be as large as 10 gigabytes in size using GnuPG.  Our tests indicate
> that it could take an hour to process a file that size on some of our
> slower hardware (Single P3 600Mhz).  It seems to be bound by processor
> speed.  (Our tests on smaller files so that disk speeds and even ramdisks
> don't make any difference.)  Does the official exe for Windows take
> advantage of multiple processors ?

It does not.  There are some things you might try to speed up the
process, though.  First of all, if you turn off compression, you save
some CPU time, though at the cost of a larger file size.  Secondly,
choose your ciphers with care.  Don't use 3DES if you can possibly
avoid it.  While it is the most highly thought of in terms of
security, it is also the slowest cipher by far.

Note that you can take advantage of multiple CPUs if you split up the
work intelligently - for example, say you want to encrypt and
compress.  If you have GnuPG encrypt, and a different program compress
then you can keep both CPUs busy.  Also, if you break your 10 gig file
into 2 5 gig files, then you can run two instances of GnuPG at once.


   David Shaw  |  dshaw@jabberwocky.com  |  WWW http://www.jabberwocky.com/
   "There are two major products that come out of Berkeley: LSD and UNIX.
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