I was using K3b on my Thinkpad laptop (300MHz PII).  I burned an ISO
image to a CDR disc, with the option "verify the MD5 checksum". 
Burning the image took 3.5 minutes.  Calculating the checksum of the
original 650MB image took some 20 minutes, and another 20 minutes to
read the disc and calcuate its checksum.  During all of this 40 minute
interval the CPU was about 100% busy.

Finding this hard to believe, I used the "md5sum" program from GNU
core utils 5.2.1 and found that it took 37 seconds to calculate the
checksum from the image.

Some Google research has turned up < http://www.equi4.com/md5/ >
"The MD5 algorithm in different programming languages".  Timings vary
by several orders of magnitude.  Chasing through the K3b sources, I
think I have found the algorithm as part of the kdecore Library, and
it seems to be written in obfuscated C++, and documented in
/usr/share/doc/HTML/en/kdelibs-apidocs\
/kdecore/html/kmdcodec_8h-source.html 

Obviously, some computers are faster than others, and if I was doing
this on a 2.8GHz P4 it would run about 10x faster.  But this is
ridiculous.

    carl
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    carl lowenstein         marine physical lab     u.c. san diego
                                                 [EMAIL PROTECTED]
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