D-LAN

h1. SHA-1 prototype

directory : source:/prototypes/01_SHA1

h2. Goals

* Compute the SHA-1 of each part of a given file.

* Compute the SHA-1 of a stream.

* Find the fastest way to compute SHA1, should be at least 40 MB/s.

h2. Speed measures

file : @01.wmv@ : 17'639'245 byte ~ 17Mo (buffered)

Each measurement is pre-runned once to put the file in cache.

h3. sha1sum from GNU coreutils (Reference)

speed : 57 MB/s

<pre>

<gburri@overnux:~/code/lang/haskell/SHA1$> time sha1sum < 01.wmv

3aec84601612e8c604ac01971e0ecd9d536dbead  -

real    0m0.301s

user    0m0.276s

sys     0m0.020s

</pre>

h3. "SHA 1.2.0":http://hackage.haskell.org/cgi-bin/hackage-scripts/package/SHA-1.2.0

file : _Hash1.hs_

speed : 4 times slower (14 MB/s)

<pre>

<gburri@overnux:~/code/lang/haskell/SHA1$> ghc --make -O2 Hash1.hs && time ./Hash1 01.wmv

[0 - 3aec84601612e8c604ac01971e0ecd9d536dbead]

real    0m1.214s

user    0m1.200s

sys     0m0.012s$

</pre>

h3. "Crypto 4.2.0":http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Crypto-4.2.0

file : _Hash2.hs_

speed : 267 times slower (1 MB/s) :

<pre>

<gburri@overnux:~/code/lang/haskell/SHA1$> ghc --make -O2 Hash2.hs && time ./Hash2 01.wmv

[0 - Word160 988578912 370337990 78381463 504286621 1399701165]

real    0m7.628s

user    0m7.576s

sys     0m0.028s

</pre>

h3. Binding with sha1.h from coreutils

file : _Hash3.hs_

TODO...