Oh, I see. We have to give up on the MerseneTwisterRNG in tests and
just use the JRE. Is that OK?
On Sat, Jan 16, 2010 at 5:44 PM, Olivier Grisel
<olivier.gri...@ensta.org> wrote:
> 2010/1/16 Drew Farris <drew.far...@gmail.com>:
>> On Sat, Jan 16, 2010 at 4:42 PM, Benson Margulies <bimargul...@gmail.com>
>> wrote:
>>> . Running through strace showed
>>>> that something was attempting to reading from /dev/random. Sometimes
>>>> it ran fine, but at least 25-30% it ended up blocking until the
>>>> entropy pool is refilled. To test I moved /dev/random, and created a
>>>> link from /dev/urandom to /dev/random (the former doesn't block, but
>>>> isn't cryptographically secure). It looks as if this could be related
>>>> to the loading of the SecureRandomSeedGenerator class.
>>>
>>> Why not use a fixed random seed for unit tests? That would make them
>>> more repeatable and avoid this problem, no?
>>>
>>
>> It appears we are. in RandomUtils:
>>
>> public static Random getRandom() {
>> return testSeed ? new MersenneTwisterRNG(STANDARD_SEED) : new
>> MersenneTwisterRNG();
>> }
>>
>> But something somewhere is forcing SecureRandomSeedGenerator to get
>> loaded by the classloader which in turn does a 'new SecureRandom()' in
>> a private static final field assignment. Trying to track down what is
>> causing the generator to get loaded in the first place.
>>
>> But something is forcing the SecureRandomSeedGenerator class to get
>> loaded, which I suspect
>>
>
>
> MersenneTwisterRNG constructor calls:
>
> this(DefaultSeedGenerator.getInstance().generateSeed(SEED_SIZE_BYTES));
>
> Which in turn calls:
>
> private static final SeedGenerator[] GENERATORS = new SeedGenerator[]
> {
> new DevRandomSeedGenerator(),
> new RandomDotOrgSeedGenerator(),
> new SecureRandomSeedGenerator()
> };
>
> In the definition of the class: DefaultSeedGenerator
>
> Unless the forking tests are disabled I don't see how to prevent the
> MersenneTwisterRNG to inderctly fetch entropy from /dev/random /
> SecureRandom.
> --
> Olivier
> http://twitter.com/ogrisel - http://code.oliviergrisel.name
>
