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Re: download rate to slow tith 1000BaseT



On Wed, Feb 27, 2013 at 05:37:36PM -0500, Mouse wrote:
> > Be careful, some SSD controllers will compress the data being stored 
> > (making$
> 
> /dev/urandom will be slow compared to doing something like arc4 in
> userland - even if the kernel implementation is fast (which it may well
> be), arc4 is cheap enough that just the syscall overhead of reading
> from /dev/urandom will probably cost more cycles than doing arc4 in
> userland.
> 
> Besides, for this even a multiplicative congruential RNG quite possibly
> would be enough.  You don't need cryptographic strength; you just need
> something random enough to defeat the SSD's compression algorithm(s).

Or one of the ones that is a bit like a CRC - but using using an
array of ints and addition (instead of single bits and xor).

        David

-- 
David Laight: david%l8s.co.uk@localhost


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