Package: dieharder
Version: 3.31.1-4
Severity: normal

Dear Maintainer,

Thanks for packaging dieharder.

I find when testing /dev/urandom using the internal interface (-g 501)
the tests 10,11,12,13,14, 201,203,204 all fail with a p-value of 0.00000000

When testing /dev/urandom via stdin, these tests usually pass.

Specifically

dieharder -d 10 -g 501
dieharder -d 11 -g 501
dieharder -d 12 -g 501
dieharder -d 13 -g 501
dieharder -d 14 -g 501
dieharder -d 201 -g 501
dieharder -d 203 -g 501
dieharder -d 204 -g 501

all fail,
whereas

cat /dev/urandom | dieharder -d 10 -g 200
cat /dev/urandom | dieharder -d 11 -g 200
cat /dev/urandom | dieharder -d 12 -g 200
cat /dev/urandom | dieharder -d 13 -g 200
cat /dev/urandom | dieharder -d 14 -g 200
cat /dev/urandom | dieharder -d 201 -g 200
cat /dev/urandom | dieharder -d 203 -g 200
cat /dev/urandom | dieharder -d 204 -g 200

usually pass.

I would have expected the results to be similar. It suggests the
internal interface to /dev/urandom is broken,
or the documenting/text is wrong, and generator 501 is NOT urandom but
something else.

The blocking pool /dev/random (-g 500) takes a lot longer to test, but
I'm getting similar results there. The internal one seems broken.
(I would not expect /dev/random to fail ANY tests of randomness!)
Feeding via stdin, /dev/random looks fine.


Example results for urandom using test 11 which is quite quick.

-----------------------------------------------------------------------------------------------------------
~$ cat /dev/urandom | dieharder -d 11 -g 200
#=============================================================================#
#            dieharder version 3.31.1 Copyright 2003 Robert G.
Brown          #
#=============================================================================#
   rng_name    |rands/second|   Seed   |
stdin_input_raw|  3.23e+06  | 159920532|
#=============================================================================#
        test_name   |ntup| tsamples |psamples|  p-value |Assessment
#=============================================================================#
    diehard_2dsphere|   2|      8000|     100|0.57695137|  PASSED  
-----------------------------------------------------------------------------------------------------------



-----------------------------------------------------------------------------------------------------------
~$ dieharder -d 11 -g 501
#=============================================================================#
#            dieharder version 3.31.1 Copyright 2003 Robert G.
Brown          #
#=============================================================================#
   rng_name    |rands/second|   Seed   |
   /dev/urandom|  1.53e+06  |1135703220|
#=============================================================================#
        test_name   |ntup| tsamples |psamples|  p-value |Assessment
#=============================================================================#
    diehard_2dsphere|   2|      8000|     100|0.00000000|  FAILED  

-----------------------------------------------------------------------------------------------------------


-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.13-1-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages dieharder depends on:
ii  libc6          2.18-4
ii  libdieharder3  3.31.1-4
ii  libgsl0ldbl    1.16+dfsg-1

dieharder recommends no packages.

dieharder suggests no packages.

-- no debconf information


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