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Date: Wed, 27 Feb 2013 09:03:43 -0800
Message-ID: <CAN4-eHJu2zx08V76FvF8vF5LMuN3RbhFb5tR+ePswdJQWcwQTw@mail.gmail.com>
Subject: Re: Is there a source of moderately random data with good speed in Cygwin?
From: Alan Thompson <thompson2526@gmail.com>
To: cygwin@cygwin.com
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On Wed, Feb 27, 2013 at 7:33 AM, Adam Dinwoodie
<Adam.Dinwoodie@metaswitch.com> wrote:
> Andrey Repin wrote:
>> I was need to pipe some bytes through application and watch it's reaction.
>> But with /dev/urandom the stream speed is only about 40Mb/sec.  Using
>> /dev/zero, however, makes it 3 orders of magnitude faster (~35Gb/s), but for
>> technical reasons, using monotonous sequence is highly undesirable.  Is there
>> any more performant source of non-monotonous byte sequences available to
>> Cygwin? I would be pretty happy even with sequential bytes, I think. Only two
>> reservations are good performance (something around 100 Mb/sec or more would
>> suffice) and a degree of randomness.
>
You could also copy one of the simple random number generators from
http://en.wikipedia.org/wiki/Linear_congruential_generator.  For
example, a simple one is

x(n+1) = (1664525 * x(n) +  1013904223) mod 2^32

Alan Thompson

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