Date: Wed, 1 Apr 2015 16:24:24 +0000 From: Alexey Dokuchaev <danfe@FreeBSD.org> To: Mateusz Guzik <mjguzik@gmail.com> Cc: Benjamin Kaduk <bjkfbsd@gmail.com>, "svn-src-head@freebsd.org" <svn-src-head@freebsd.org>, "svn-src-all@freebsd.org" <svn-src-all@freebsd.org>, "src-committers@freebsd.org" <src-committers@freebsd.org>, Mark R V Murray <mark@grondar.org> Subject: Re: svn commit: r280955 - in head/sys: modules/notrandom dev/notrandom Message-ID: <20150401162424.GB85612@FreeBSD.org> In-Reply-To: <20150401154633.GA14631@dft-labs.eu> References: <20150401113628.GA16649@dft-labs.eu> <20150401114313.GZ64665@FreeBSD.org> <20150401115204.GB16649@dft-labs.eu> <1427897897.82583.62.camel@freebsd.org> <551C0A92.8070507@freebsd.org> <551C0B2A.9060006@freebsd.org> <5A609CED-56E6-4459-8505-58930048AA0D@grondar.org> <CAJ5_RoAAnV8bTUeD-Okdy2JJkUyyS3Fy%2BhrP8kKz0s=nZG615g@mail.gmail.com> <20150401154633.GA14631@dft-labs.eu>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Apr 01, 2015 at 05:46:33PM +0200, Mateusz Guzik wrote: > On Wed, Apr 01, 2015 at 11:36:26AM -0400, Benjamin Kaduk wrote: > > But surely to be non-random we need an equal number of 1 and 0 bits, > > making 15 the clear choice. > > I don't know man. I concur. Consider running FreeBSD to HP48; 15 would max out entire nibble, leading to predictability and risk of overflow attacks. > First off, '7' could not be chosen at random. I'm convinced factors like > amount of CPUs (and their speed), RAM etc. played a huge factor here. > > Now that everything is faster these days, one could ponder returning > '8'. OTOH, eight also fits two elementary units (trits) on trinary machines, which might allow for certain micro-optimizations when you need strong flow of non- random numbers. > We can add an ioctl to control this. > > Opinions? To stay portable, very likely, yes. ./danfe
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20150401162424.GB85612>