> adrelanos@??? wrote (18 Dec 2012 22:18:28 GMT) :
>>> Hi,
>>>
>>> adrelanos wrote (16 Dec 2012 18:19:44 GMT) :
>>>> - Do they block each other or result in even more entropy available?
>>>> [...]
>>>> haveged only ~1100 and ~4000
>>>> randomsound and haveged ~1100 and ~4000
>>>
>>> Isn't this capped by /proc/sys/kernel/random/poolsize ?
>
>> No.
>> https://www.kernel.org/doc/man-pages/online/pages/man4/random.4.html
>
> Thanks.
>
> The read-only file entropy_avail gives the available entropy.
> Normally, this will be 4096 (bits), a full entropy pool.
>
> The file poolsize gives the size of the entropy pool.
> The semantics of this file vary across kernel versions:
> [...]
> Linux 2.6: This file is read-only, and gives the size of
> the entropy
> pool in bits. It contains the value 4096.
>
> I admit I've not checked the code, but in my understanding of this
> documentation, it confirms the available entropy is capped by the
> entropy pool size.
cat /proc/sys/kernel/random/poolsize is always 4096. Unusable for
benchmarking.
cat /proc/sys/kernel/random/entropy_avail numbers always change. Depends
on hardware (real or virtual). Also depending on which entropy related
packages are installed they change even more.
I didn't check the kernel sources either, but this is backed up by
practical tests and instructions on how to benchmark it everywhere. There
is a consensus.
http://manyrootsofallevilrants.blogspot.co.at/2011/06/rng-utils-and-entropy-rhel6-style.html
http://pthree.org/2012/09/14/haveged-a-true-random-number-generator/