Re: [PATCH 1/3] Make /dev/urandom scalable

From: Jeff Epler
Date: Thu Sep 24 2015 - 16:00:45 EST

On Thu, Sep 24, 2015 at 03:11:23PM -0400, Austin S Hemmelgarn wrote:
> I will make a point however to run some tests over the weekend on a
> current kernel version (4.2.1), with the current dieharder version I
> have available (3.31.1).

Please report your findings. If urandom is worse than AES_OFB in
statistical tests, we need to know about it.

I'm an hour into some test-to-failure runs of diehard_count_1s_str on
various RNGs -- urandom, AES_OFB, mt19937_1999, and rand48. So far at
psamples >=29000 none have failed, so there's no result to report. (test
8 was chosen by mere human pseudorandomness; hey, it finds in <2s that
RANDU is a flawed generator)

dieharder -d 8 -g 205 -Y 2 -k 2
dieharder -d 8 -g 200 -Y 2 -k 2
dieharder -d 8 -g 14 -Y 2 -k 2
dieharder -d 8 -g 22 -Y 2 -k 2

If the results are other than "both urandom and aes_ofb were running
when I had to reboot my laptop", I'll report my results as well.

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